The anorthositic rocks in southern part of Korean peninsula occur as a long belt, intruding the ca . 2.0 Ga old Precambrian basement rocks of the Yeongnam massif. Although they have simple rock types (anorthosite and gabbroic anorthosite) comparable to well known massif-type anorthosites worldwide, they possess several important differences such as layered structure, amphibole rather than pyroxene as a mafic phase, and no orthopyroxene megacrysts. Theage of intrusion was not available previously. We have applied Rb-Sr and Sm-Nd isotope systematics to investigate the age and origin of these rocks. One foliated gabbroic anorthosite defines a Sm-Nd mineral isochron age of 1678±90 Ma. This age is tentatively interpreted as the emplacement age because of apparently closed-system behavior of Sm-Nd system in these rocks during greenschist-facies metamorphism of presumably Mesozoic age. This age agrees with the age range (1.1 to 1.7 Ga) reported for the occurrence of Proterozoic massif-type anorthosites, suggesting that origin of the anorthositic rocks might be explained in the context of so-called Proterozoic anorthosite event. Significance of the anorthositic magmatism to the tectonic history of the Precambrian basement rocks in southern Korea Peninsula is discussed. εNd(t) values of whole rocks range -1.6 to -5.2, while initial 87Sr/86 Sr ratios vary from 0.704 to 0.706. These data are interpreted as the result of assimilation of crustal material during crystallization of presumed anorthositic magma of mantle origin, although possible lower crustal source can not be excluded.