PURPOSE: To obtain microcapsules having superior shelf stability by emulsifying or dispersing a mixture of a lipophilic substance with a polyisocyanate compd. in an aq. methylcellulose soln. and adding urea and formaldehyde.

CONSTITUTION: A mixture of a lipophilic substance with at least one kind of compd. selected among a polyisocyanate compd., a polyisothiocyanate compd. and prepolymers of them is emulsified or dispersed in an aq. methylcellulose soln. Urea and formaldehyde or methylolurea are added to the emulsified or dispersed aq. soln. and this soln. is heated in an acidic state. By this heating, polymer walls are formed around the particles of the lipophilic substance and microcapsules are produced. The polyisocyanate compd. or the like is preferably used by 0W50pts.wt. per 100pts.wt. lipophilic substance.