Melianoninol (I), melianol (II), melianone (III), meliandiol (IV), vanillin (V) and vanillic acid (VI) were isolated from the fruits of Melia azedarach L.. The structure of melianoninol, a new compound, was elucidated by IR, MS, 1H NMR, 13CNMR and other spectral evidences. The new compound possesses