Food safety has always been and continues to be a major concern for all countries of the world. This concern is all the more perennial in the developing countries like Benin with a low economic level and still rudimentary and extensive agriculture. To reduce a little bit of food insufficiency, is developed urban and peri-urban agriculture based mainly on market gardening. This study focused particularly on the production of onion in southern Benin. It aims to analyze its performance, to understand the importance of this activity but also to see what are the obstacles faced by these producers. Three municipalities were investigated: Grand-Popo, Cotonou and Sèmè-Kpodji. A total of 60 farmers were surveyed at 20 per municipality. Quantitative and qualitative tools were combined for the analysis of data collected through individual and group interviews. A joint analysis approach was used to achieve specific objectives. It consists to combine speech analysis, participant observation with statistical tools such as the frequency distribution, the regression model and calculation of performance indicators. It follows from all of these analyzes that onion production is profitable from a financial point of view. This performance is enhanced by factors such as age, experience and membership of a producer group. Similarly, the farmers claimed for majority that onion occupies a special place in their market garden production. This production improves their socio-economic and food situations. However, the constraints that undermine the more onion production and thus constitute important producer concerns are financial, institutional, organizational, property constraints and those directly related to production. Farmers therefore, expect a little more effort from agricultural policies to improve the development of this sector.