Two hundred fourteen (214) married persons, 101 men and 113 women aged 20-60, with at least high school education, participated in the study which investigated the effects of gender, age, and educational attainment on assertiveness among married persons in Nigeria. The Assertive Behavior Assessment scale (ABAS; Onyeizugbo, 1998) was used to measure assertiveness. It was hypothesized that persons with higher educational attainment will report more assertiveness than persons with lower educational attainment. Results supported the hypothesis. In addition, interactions between gender and age, and gender and educational attainment were found. Younger men reported more assertiveness than younger women whereas older women reported more assertiveness than older men. Also, women participants of lower educational attainment reported more assertiveness than their men counterparts whereas men of higher educational attainment reported more assertiveness than their women counterparts. Results of this study suggest that women in Nigeria may become more assertive with age. (Contains 2 figures.)