As important as smallholders are to food production across in sub-Saharan Africa, smallholders face a lot of challenges in accessing market. This study examined the determinants of market participation among smallholders rice farmers in a major rice producing Local government area of Ogun State, Nigeria. The result showed that all the sampled farmers participated in the output market with the mean participation put at 89%. The fractional Probit regression showed farm size, formal education, fertilizer application, land ownership through inheritance and cost of transportation as significant determinants of level of output market participation. In order to enhance market participation, the study recommends provision of good transport facilities which is capable of reducing transport cost, removal of bottlenecks preventing access to and use fertilizer as well as provision of farm land in manners similar to inheritance which makes land available at low/zero cost and reduces land fragmentation . Acknowledgement :