Exhibit 31.2

CERTIFICATION OF PRINCIPAL ACCOUNTING OFFICER

PURSUANT TO SECTION 302 OF THE

SARBANES-OXLEY ACT OF 2002

I, Irving H Kau, certify that:

1. I have reviewed this amended Annual Report on Form 10-K/A of Focus Universal Inc. for the year ended December 31, 2023; and

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report.