Gather your documents. Passport forms are available for download on the embassy website. You will need an official copy of your long form birth certificate. If you don't have access to it, the embassy can help you obtain a copy prior to making your application. You will also need to present your Zimbabwe National identity Card, your passport, and two photocopies of the last page and visa page of the passport.
Verify that all information matches. All names listed on your documents must match and be in the same order on each. If they don't, contact the embassy by phone for instructions on how to correct the issue. New, corrected documents may need to be ordered prior to making your application.
Visit the embassy and make your application in person. You will need to apply in person with all proper documentation in order to renew your passport.