Fifty male and 106 female largemouth bass were injected with human chorionic gonadotropin (HCG) during the 1972 and 1973 spawning seasons. Milt production was increased or maintained in 80% of the males tested. and 63% of the females ovulated. Females with spent or immature gonads did not noticeably respond to HeG injections. Females tested during the latter half of both spawning seasons demonstrated lower percentages of successful ovulations and reduced numbers of eggs per ovulation. Ninety percent of the ovulated females required only one injection, whereas nearly half of the females that resorbed their eggs required two injections before resorption could be determined. Results indicate that some females can be ovulated twice or three times with multiple injections, but that the success rate is too low to enable practical application. Most females ovulated within 48 hours of injection. Ovulated eggs, if not stripped and fertilized, became inviable within 12 to 16 hours of ovulation.