A field study was conducted to evaluate the effects of ambient ozone on the yield quantity and quality of the pods of four legume crops (Pisum sativum L., Vicia faba L., Glycine max and Vigna sinensis) grown under five ambient ozone concentrations: 17.80, 61.00, 71.50, 78.75 and 111.78 ppb and 21.25, 67.25, 96.5, 105.5 and141.25 ppb during winter and summer, respectively. The ozone levels significantly affected the yield of both the winter and summer species. As the ozone concentration increased, the number and dry weight of the pods decreased. The plants varied in their yield responses to stress; however, the degree of damage in all of the species was more severe under elevated ozone. The protein, fat, soluble sugar and polysaccharide content were significantly different in the pods. This investigation recorded high ozone concentrations at the studied sites with a high source of air pollution, especially during the summer, and demonstrated the negative effect of ozone on the yield quantity and quality of the tested species.