Abstract The activity and kinetic properties of urease in several Malaysian soils were examined. The values for K m and V max of the soils computed according to the Hanes equation were in general agreement with other reports as far as magnitudes were concerned. A significant correlation between K m and V max was also obtained. The urease activity of the soils was variable, and it was noted that expression of the activity as the time required to hydrolyze half of the applied urea has limited use in soils of low activity. In all soils studied, inhibition of urease activity was effectively achieved using Ag +, while Cu 2+ was only effective in two soils, and marginally effective in the other two soils. Urease inhibitors have potential applications in reducing volatilization losses of ammonia derived from urea applied to soils.