The Cr isotopic composition of primitive meteorites (acid-residue fractions) was studied. Five chondrites were analyzed in this work [Allende (CV3), Murchison (CM2), Nuevo Mercurio (H5), La Criolla (L6), Qingzhen (EH3)]. Although in most samples, no isotopic anomalies beyond the experimental errors could be detected, an elevated 54 Cr/ 52 Cr ratio was found in the acid-soluble fraction from Qingzhen. Moreover, t: 53 Cr and t: 54 Cr show an inverse correlation among the meteorites analyzed in

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... s study, and the acid residues have larger t: 54 Cr and small er t: 53 Cr values than do the acid-soluble fractions in Allende and Murchison. The enrichment of 54 Cr in the Qingzhen sample suggests that the 54 Cr heterogeneity due to stellar nucleosynthesis has remained in enstatite chondrite as well as carbona ceous chondrite. In addition, the inverse correlation of t: 53 Cr and t: 54 Cr detected in acid residue samples indicates that the high-temperature condensate contained more exotic 54 Cr. It is also suggested that the homogenization of Cr isotopes proceeded with time, and terminated within a relatively short time scale of less than 2-3 Ma.