A field experiment was carried out during 2020 and 2021 seasons at Al-Marashda Agricultural Research Station, Qena Governorate, A.R.C, Egypt. The objective of this work was to evaluate the yield and its components as well as seed protein and oil content in four soybean genotypes to foliar application of different proline levels. The four studied soybean genotypes were, Giza 111, H18L54, H1L3, and H3L4, while the four concentrations of proline were 0, 25, 50, and 75 ppm. The field experiment was assigned in a strip plot design with three replications. Proline concentrations were allocated horizontally while soybean genotypes were distributed vertically. The obtained results indicated that the foliar application of proline levels caused a significant increase in the yield and its components as well as studied chemical traits of soybean genotypes compared to untreated plants in favor of 50 ppm concentration. Moreover, the highest mean values of soybean yield were recorded with Giza 111 followed by H18L54 genotypes in the first and second seasons, respectively. It was noticed that foliar application of proline at the rate of 50 to G111 genotypes resulted in the highest mean values of yield parameters as well as protein and oil percentage traits in both seasons.