Abstract: Knowledge of plant available fractions of heavy metals in soil can assist directing phytoremediation efforts for contaminated soils. For this reason different doses of ZnCl2 (0, 200, 400 and 600 mg kg-1) and CdCl2, 2½ H2O (0, 9, 18 and 27 mg kg-1) were applied to an uncontaminated slightly acidic clay loam soil from Sate of Mexico, Mexico incubated under ambient temperature and humidity for 90 days. Both the metals were extracted with a DTPA-TEA-CaCl2 mixture after 1, 5, 15, 25, 60 and 90 days and analyzed using atomic absorption spectroscopy. The results showed that DTPA extractable contents of Zn and Cd followed a decreasing trend with increase in incubation time. Maximum contents were found at day 01 in all the treatments. After 15 days of incubation, the variation in extractable contents was non-significant. The rapid adsorption of the metals might be due to elevated clay content (34%) of the incubated soil.