Though Bench Sheko and Sheka zones have great potential for dairy production in Ethiopia, the majority of dairy producers’ could not get benefit from the sector in a sustainable way due to the low market participation problem. Hence, this study was designed to analyze determinants of market participation by dairy producers’ in Southwestern Ethiopia. Data from 160 sampled dairy producers were employed and analyzed by using the probit model. The model result shows the ownership of crossbreeds, utilization of improved livestock feeds and size of dairy cows’ ownership affect market participation decisions significantly and positively. While the number of children below six years and distance from the market is the significant factors determining the likelihood of dairy market participation negatively in southwestern Ethiopia. Therefore, demonstrations of improved livestock breed through supplying improved bulls and artificial insemination technologies, demonstration of improved livestock forages and concentrates through training, and organizing dairy marketing cooperative and dairy products collection centers are suggested to improve the market participation in the study area.