The effect of La on nitrification, P transformation and phenol decomposition in red soil was studied by incubation and pot culture experiments. La at low concentration has stimulative effect on soil nitrification and P transformation while its high concentration has inhibitory effects, and the inhibition is strengthened with increasing concentration of La. La has strongly inhibitory effect on soil phenol decomposition and the inhibition is strengthened with increasing concentration of La. When the incubation time is prolonged, the inhibitory effect of La on soil nitrification and phenol decomposition tends to decrease.