The present invention relates to a novel 1,3-diphenylpropane derivative having an inhibitory activity against tyrosinase represented by the following formula (I): ##STR1## in which - - represents double or single bond, R.sub.1 represents hydrogen or C.sub.1 -C.sub.10 alkyl, R.sub.2 represents C.sub.1 -C.sub.5 alkyl or C.sub.1 -C.sub.5 alkoxyalkyl, or R.sub.1 and R.sub.2 together represent a 5 to 6 membered heterocycle which can be substituted by C.sub.1 -C.sub.5 alkyl and which contains oxygen as the hetero atom, R.sub.3 represents hydrogen or C.sub.1 -C.sub.7 alkyl, R.sub.4 represents hydrogen, hydroxy, or oxo, and R.sub.5 and R.sub.6 mindependently of one another represent hydrogen or C.sub.1 -C.sub.5 alkyl.