PROBLEM TO BE SOLVED: To obtain a beautifully whitening agent capable of being easily dissolved or dispersed in water, oils or other media and free from a specific smell by including cinnamic acid (derivative) and cyclodextrin. SOLUTION: This beautifully whitening agent contains (A) cinnamic acid (derivative) and (B) cyclodextrin(CD) in an amount of 1-10 moles per mole of the component A preferably in the form of their clathrate compound. The cinnamic acid derivative of component A is preferably a p-methoxycinnamic acid ester, caffeic acid, etc. The component B is preferably α, β and γ-CDs produced in the presence of a CD-producing enzyme produced from a microorganism and maltosylated α, β and γ-CDs. The components A and B are preferably contained in amounts of 0.01-20 wt.% and 0.1-15 wt.%, respectively, in the beautifully whitening agent.