A composition for controlling plant diseases comprising a tetrazolinone compound represented by a formula (1):wherein n is an integer of any one of 0 to 5 R1 represents a halogen atom and the like R2 represents a C1-C3 alkyl group and the like the R1 or R2 can have independently halogen atom(s) in the alkyl moiety with the proviso that when n is an integer of 2 or more, two or more of the R1 may be different from each other, and an azole compound, preferably the composition for controlling plant diseases wherein a weight ratio of the tetrazolinone compound to the azole compound is that of the tetrazolinone compound/the azole compound=0.1/1 to 10/1, shows an excellent controlling efficacy on plant diseases.
