Traditionally, the Mianxian—Lueyang mélange(MLM) was interpreted to be a suture when the south and north China blocks collided in the early Mesozoic. The ophiolitic and mafic blocks in the MLM were considered as the remnants of a Devonian regenerated oceanic basin.SHRIMP UPb analyses for zircon grains in this paper showed that the ophiolitic blocks (sample SCZ11, XKY8 and GYY1) in the Kangxian—Mianxian section of the MLM were formed in the Neoproterozoic, ca 841±16~812±11Ma. SHRIMP dating results yielded ages of 827±14~808±10Ma to the mafic blocks (sample B126, B136 and B175) in the MLM.However, a plagiogranite block (sample SCZ9) in the middle of the MLM near a small town Sancazi was dated at ca 923±13Ma, significantly older than other ophiolitic and mafic blocks. The ages of the ophiolitic and mafic blocks are greatly excellent with each other within the errors. As a result, the update results in the present paper indicated that those ophiolitic and mafic blocks in the MLM are actually the remnants of a Neoproterozoic ocean basin, rather than the socalled Devonian regenerated ocean basin as previously.