A study was conducted to determine the effectiveness of male and female extension agents in reaching farmers, especially women, with extension services in Nigeria. Specially the study determined the levels of awareness of and participation in extension activities, adoption of and technical knowledge of recommended agricultural technologies/practices, satisfaction with the quality of extension services provided and agents' credibility of men and women farmers under male and female extension agents supervision. Data gathered from 141 men and 72 women farmers supervised by male agents and 22 men and 93 women farmers supervised by female agents in Oyo, Kaduna and Rivers State Agricultural Development Projects in Nigeria form the empirical basis for the study. Even though men farmers are more aware of and participated more in the extension activities organised by agents than women farmers, the study shows that women farmers, who are supervised by female agents have more access to extension services than women farmers who work with male agents. Specifically, women farmers, who had females for extension agents had relatively higher levels of awareness and participation of the extension activities organised, adoption of and technical knowledge of recommended technologies/practices and satisfaction with the quality of agents' services and credibility. These differential effects of female and male agents on women's access to extension are significant for the delivery of extension services to women farmers, especially. Extension organisations must encourage and recruit more females for extension work done at the same time evolve strategies that will help male agents to work better with women farmers.