WASHINGTON—Democratic presidential candidate Andrew Yang, a self-described tech entrepreneur and philanthropist, earned about $150,000 last year, according to his newly released personal financial disclosure form.

The form shows the 44-year-old’s earnings last year came mostly from speaking engagements, including at the investment bank JPMorgan Chase & Co., and that he has assets worth between about $834,000 and $2.4 million, mostly tied to a Hudson Valley property.

Though...