This invention provides a polylactic acid resin composition in which stereocomplex crystals of poly-L-lactic acid and poly-D-lactic acid can be selectively crystallized to obtain polylactic acid having a sufficiently high speed of crystallization and a sufficiently high ratio of stereocomplex crystal and a molded article thereof obtained via melt molding and crystallization of the same. Such polylactic acid resin composition comprises polylactic acid capable of generating stereocomplex crystallization and an aromatic urea compound represented by formula (1): wherein R1 represents an alkylene group having 1 to 10 carbon atoms; R2 represents an alkyl group having 1 to 25 carbon atoms; and m is an integer between 1 to 6.