To obtain extremely excellent catalytic activity in the oxidation of olefins with hydrogen peroxide as an oxidizing agent which can be easily handled and to efficiently and easily produce oxides of olefins (epoxides, noles, nones, aldehydes or the like).

This catalyst for oxidation of olefins consists of a mesopore titanosilicate molecular sieve and contains org. carbon groups directly bonded to silicon atoms of the titanosilicate skeleton which constitutes the molecular sieve. The amt. of the org. carbon groups is 0.01 to 0.6 mol to one mol of silicon oxide. The catalyst consists of a mesopore titanosilicate molecular sieve which is a porous body having uniform pore diameter in 1.5 to 10 nm range in the mesopore region and which has org. carbon groups directly bonded to silicon which constitutes the skeleton of the body.