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Objective: To evaluate the tolerance of four genotypes of Medicago sativa L. to salinity and cadmium, through the study of germination, growth parameters, photosynthetic pigments, and osmocompatible response. Materials and methods: The experimental design was a completely randomized design with a factorial arrangement: type of genotype: CW 197, Trinidad 87, CW 660 and Salina PV and levels of saline (NaCl) and cadmium (Cl2Cd) stress. Factorial ANOVA was performed to identify the influence of stress conditions on the measured variables, multiple comparisons analyse of means were performed when a significant effect was found. Twenty seeds were sown in triplicate irrigated with water (control) and solutions between 10 to 200 mM of NaCl and 100 to 500 jU, M of Cl2Cd for the germination study. Growth, proline, and photosynthetic pigments were measured in 4-week-old seedlings grown in pots irrigated with nutrient solution (control) and increasing concentrations of NaCl (50-200 mM) and Cl2Cd (25-100/iM). Results: Under salinity, the CW179 and CW660 genotypes were tolerant to salinity at germination, and the Salina PV and Trinidad 87genotypes were more tolerant during growth. In response to Cd, the genotypes showed tolerance during growth. Proline was osmoprotective against salinity, but not against Cd stress. Photosynthetic pigments decreased with salt stress; however, Cd did not affect them. Conclusion: The CW 660 genotype was the most tolerant to salinity and Cd during germination. It is concluded that the Trinidad 87 and Salina PV genotypes are tolerant to salt and the CW 197 and CW 660 genotypes are sensitive during growth. Under Cd stress, all genotypes showed tolerance during growth. Proline and photosynthetic pigments were indicators of tolerance to salt stress. [ABSTRACT FROM AUTHOR]