A cross-sectional study was conducted to determine knowledge and attitudes toward organ donation and transplant in Lagos, Nigeria. The study sample was selected through a multistaged sampling technique. The survey instrument was a standardized self-administered questionnaire. Four hundred and twenty-eight subjects participated in the study. The mean age was 31.1 +/- 2.1 years. Two hundred and fifty-six (60%) were aware of organ donation. Renal failure was the most commonly identified indication for transplant. One hundred and twenty-seven (30%) subjects were willing to donate an organ. Knowledge about organ donation was significantly higher among those with tertiary level of education (P = 0.000). Willingness to donate an organ showed a significant relationship with younger age (P = 0.002), but not with gender (P = 0.47) or educational status (P = 0.09). There is a need to increase awareness about organ donation in Lagos, Nigeria.