Exhibit 99.3

OSTIN TECHNOLOGY GROUP CO., LTD. BUILDING 2, 101/201 1 KECHUANG ROAD QIXIA DISTRICT, NANJING JIANGSU PROVINCE, CHINA 210046 SCAN TO VIEW MATERIALS & VOTE VOTE BY INTERNET - www.proxyvote.com or scan the QR Barcode above Use the Internet to transmit your voting instructions and for electronic delivery of information up until 11:59 p.m. Eastern Time the day before the cut-off date or meeting date. Follow the instructions to obtain your records and to create an electronic voting instruction form. ELECTRONIC DELIVERY OF FUTURE PROXY MATERIALS If you would like to reduce the costs incurred by our company in mailing proxy materials, you can consent to receiving all future proxy statements, proxy cards and annual reports electronically via e-mail or the Internet. To sign up for electronic delivery, please follow the instructions above to vote using the Internet and, when prompted, indicate that you agree to receive or access proxy materials electronically in future years. VOTE BY PHONE - 1-800-690-6903 Use any touch-tone telephone to transmit your voting instructions up until 11:59 p.m. Eastern Time the day before the cut-off date or meeting date. Have your proxy card in hand when you call and then follow the instructions. VOTE BY MAIL Mark, sign and date your proxy card and return it in the postage-paid envelope we have provided or return it to Vote Processing, c/o Broadridge, 51 Mercedes Way, Edgewood, NY 11717. TO VOTE, MARK BLOCKS BELOW IN BLUE OR BLACK INK AS FOLLOWS: V22686-P98546 KEEP THIS PORTION FOR YOUR RECORDS THIS PROXY CARD IS VALID ONLY WHEN SIGNED AND DATED. DETACH AND RETURN THIS PORTION ONLY OSTIN TECHNOLOGY GROUP CO., LTD. The Board of Directors recommends you vote FOR the following proposal: 1. Re-election of Directors Nominees: For Against Abstain 1a. Tao Ling 1b. Xiaohong Yin 1c. Heung Ming Wong 1d. John Carl Mein 1e. Qiang He The Board of Directors recommends you vote FOR the following proposal: 2. To approve, ratify, and confirm the re-appointment of TPS Thayer, LLC as the Company’s independent registered public accounting firm for the fiscal year ending September 30, 2023. NOTE: Such other business as may properly come before the meeting or any adjournment thereof. Please sign exactly as your name(s) appear(s) hereon. When signing as attorney, executor, administrator, or other fiduciary, please give full title as such. Joint owners should each sign personally. All holders must sign. If a corporation or partnership, please sign in full corporate or partnership name by authorized officer. Signature [PLEASE SIGN WITHIN BOX] Date Signature (Joint Owners) Date For Against Abstain

Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting: The Proxy Statement is available at www.proxyvote.com. V22687-P98546 OSTIN TECHNOLOGY GROUP CO., LTD. Annual Meeting of Shareholders September 28, 2023, at 8:00 P.M., Beijing Time This proxy is solicited on behalf of the Board of Directors The shareholder(s) hereby appoint(s) Tao Ling, as proxy, with the power to appoint his substitute, and hereby authorize(s) him to represent and to vote, as designated on the reverse side of this ballot, all ordinary shares of OSTIN TECHNOLOGY GROUP CO., LTD. that the shareholder(s) is/are entitled to vote at the Annual Meeting of Shareholders to be held at 8:00 P.M., Beijing Time on September 28, 2023, at Building 2, 101/201, 1 Kechuang Road, Qixia District, Nanjing, Jiangsu Province, China 210046, and any adjournment or postponement thereof. This proxy, when properly executed, will be voted in the manner directed herein. If no such direction is made, this proxy will be voted in accordance with the Board of Directors’ recommendations. Continued and to be signed on reverse side