UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

o

Rule 13d-1(b)

o

Rule 13d-1(c)

x

Rule 13d-1(d)

1

Name of Reporting Person
Glory Achievement Fund Limited

2

Check the Appropriate Box if a Member of a Group

(a)

o

(b)

o

3

SEC Use Only

4

Citizenship or Place of Organization
Cayman Islands

Number of
Shares
Beneficially
Owned by
Each
Reporting
Person With

5

Sole Voting Power
59,014,235

6

Shared Voting Power
0

7

Sole Dispositive Power
59,014,235

8

Shared Dispositive Power
0

9

Aggregate Amount Beneficially Owned by Each Reporting Person
59,014,235

10

Check if the Aggregate Amount in Row (9) Excludes Certain Shares  o

11

Percent of Class Represented by Amount in Row 9
39.7%. *The voting power of the shares beneficially owned represent 28.0% of the total outstanding voting power.

12

Type of Reporting Person
CO

1

Name of Reporting Person
Bull Group Limited

2

Check the Appropriate Box if a Member of a Group

(a)

o

(b)

o

3

SEC Use Only

4

Citizenship or Place of Organization
Cayman Islands

Number of
Shares
Beneficially
Owned by
Each
Reporting
Person With

5

Sole Voting Power
59,014,235

6

Shared Voting Power
0

7

Sole Dispositive Power
59,014,235

8

Shared Dispositive Power
0

9

Aggregate Amount Beneficially Owned by Each Reporting Person
59,014,235

10

Check if the Aggregate Amount in Row (9) Excludes Certain Shares  o

11

Percent of Class Represented by Amount in Row 9
39.7%. *The voting power of the shares beneficially owned represent 28.0% of the total outstanding voting power.

12

Type of Reporting Person
CO

1

Name of Reporting Person
BULL TRUST

2

Check the Appropriate Box if a Member of a Group

(a)

o

(b)

o

3

SEC Use Only

4

Citizenship or Place of Organization
Hong Kong

Number of
Shares
Beneficially
Owned by
Each
Reporting
Person With

5

Sole Voting Power
59,014,235

6

Shared Voting Power
0

7

Sole Dispositive Power
59,014,235

8

Shared Dispositive Power
0

9

Aggregate Amount Beneficially Owned by Each Reporting Person
59,014,235

10

Check if the Aggregate Amount in Row (9) Excludes Certain Shares  o

11

Percent of Class Represented by Amount in Row 9
39.7%. *The voting power of the shares beneficially owned represent 28.0% of the total outstanding voting power.

12

Type of Reporting Person
OO

Item 1(a).

Name of Issuer:

Niu Technologies (the “Issuer”)

Item 1(b).

Address of Issuer’s Principal Executive Offices:

No. 10 Wangjing Street, Building A, 11/F Chaoyang District, Beijing 100102, People’s Republic of China

Item 2(a).

Name of Person Filing:

Glory Achievement Fund Limited

Bull Group Limited

BULL TRUST

(collectively, the “Reporting Persons”)

Item 2(b).

Address of Principal Business Office or, if none, Residence:

Glory Achievement Fund Limited
P.O. Box 2075, George Town, Grand Cayman KY1-1105, Cayman Islands

Bull Group Limited

at the offices of Maricorp Services Ltd., P.O. Box 2075, #31 The Strand, 46 Canal Point Drive, Grand Cayman KY1-1105, Cayman Islands.

BULL TRUST

ARK Trust (Hong Kong) Limited as trustee

Room 01-04, 15/F, One Exchange Square, 8 Connaught Place, Central, Hong Kong

Item 2(c)

Citizenship:

Glory Achievement Fund Limited — Cayman Islands

Bull Group Limited — Cayman Islands

BULL TRUST — Hong Kong

Item 2(d).

Title of Class of Securities:

Ordinary shares, $0.0001 par value per share, of the Issuer

The Issuer’s ordinary shares consist of Class A ordinary shares and Class B ordinary shares. Each holder of Class A ordinary shares is entitled to one vote per share and each holder of Class B ordinary shares is entitled to four votes per share on all matters submitted to them for vote. Class B ordinary shares are convertible at any time by the holder thereof into Class A ordinary shares on a one-for-one basis. Class A ordinary shares are not convertible into Class B ordinary shares under any circumstances.

Item 2(e).

CUSIP Number:

65481N 100

This CUSIP number applies to the American depositary shares of the Issuer, each representing two Class A ordinary shares of the Issuer. No CUSIP has been assigned to the ordinary shares.

Item 3.

If this statement is filed pursuant to §§240.13d-1(b), or 240.13d-2(b) or (c), check whether the persons filing is a:

Not applicable

Item 4.

Ownership:

The following information with respect to the ownership of the ordinary shares of par value of $$0.0001 per share of Issuer by each of the Reporting Persons is provided as of December 31, 2018:

Reporting Person

Amount
beneficially
owned:

Percent of
class:

Sole power
to vote or
direct
the vote:

Shared
power to
vote or to
direct the
vote:

Sole power
to dispose or
to direct the
disposition
of:

Shared
power to
dispose or to
direct the
disposition
of:

Glory Achievement Fund Limited

59,014,235

39.7

%

59,014,235

0

59,014,235

0

Bull Group Limited

59,014,235

39.7

%

59,014,235

0

59,014,235

0

BULL TRUST

59,014,235

39.7

%

59,014,235

0

59,014,235

0

As of December 31, 2018, Glory Achievement Fund Limited, a Cayman Islands company, held 59,014,235 Class A ordinary shares of the Issuer. Glory Achievement Fund Limited is wholly owned by Bull Group Limited, a Cayman Islands company.  Bull Group Limited is wholly owned by BULL TRUST, which has Mr. Yi’nan Li as the beneficiary and is administered by an independent trustee and initially by three individual protectors unrelated to Mr. Li. Any decision making with respect to the voting or disposal of the shares held by Glory Achievement Fund Limited in the Issuer or other dealings in the Issuer’s securities is subject to approval by the protectors. Mr. Yi’nan Li will be able to replace the protectors with persons appointed by himself in August 2028 or when the trust beneficially owns, through Glory Achievement Fund Limited or otherwise, no more than 10% of the outstanding shares of the Issuer on an as-converted basis.

The percentage of class of securities beneficially owned by each of the Reporting Persons as of December 31, 2018 is based on a total of 148,674,058 outstanding ordinary shares (being the sum of 128,032,038 Class A ordinary shares and 20,642,020 Class B ordinary shares) of the Issuer outstanding  as a single class as of December 31, 2018, assuming conversion of all Class B ordinary shares into Class A ordinary shares. Class B ordinary shares are convertible at any time by the holder thereof into Class A ordinary shares on a one-for-one basis, whereas Class A ordinary shares are not convertible into Class B ordinary shares under any circumstances.

Item 5.

Ownership of Five Percent or Less of a Class:

Not applicable

Item 6.

Ownership of More than Five Percent on Behalf of Another Person:

Not applicable

Item 7.

Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company or Controlling Person:

Not applicable

Item 8.

Identification and Classification of Members of the Group:

Not applicable

Item 9.

Notice of Dissolution of Group:

Not applicable

Item 10.

Certifications:

Not applicable

Exhibit No.

Description

A

Joint Filing Agreement

GLORY ACHIEVEMENT FUND LIMITED

By:

/s/ Peng Zhang

Name:

Peng Zhang

Title:

Director

BULL GROUP LIMITED

By:

/s/ WANG Jing and NG Sung Yan

Name: WANG Jing and NG Sung Yan

Title: Authorized Signatories

For and on behalf of

Helm Management Limited

Corporate Director

BULL TRUST

By:

/s/ WANG Jing and NG Sung Yan

Name: WANG Jing and NG Sung Yan

Title: Authorized Signatories

For and on behalf of

ARK Trust (Hong Kong) Limited

Trustee

GLORY ACHIEVEMENT FUND LIMITED

By:

/s/ Peng Zhang

Name:

Peng Zhang

Title:

Director

BULL GROUP LIMITED

By:

/s/ WANG Jing and NG Sung Yan

Name: WANG Jing and NG Sung Yan

Title: Authorized Signatories

For and on behalf of

Helm Management Limited

Corporate Director

BULL TRUST

By:

/s/ WANG Jing and NG Sung Yan

Name: WANG Jing and NG Sung Yan

Title: Authorized Signatories

For and on behalf of

ARK Trust (Hong Kong) Limited

Trustee