The study carried out the isotopic geochronology of Cretaceous continental “red layer” volcanic rock in Wanjia- Lancun area from Jiaolai basin to determine the formation age and the petro- genesis, to divide rock formation units. Based on the zircon U- Pb dating research, the harmonic linear intersection age value of 11832±073 Ma (MSWD=100) is obtained for 24 points, which represents the formation time of rhyolitic welded tuff. The sedimentary age of the “red layer” of the terrestrial phase of the Cretaceous period is the Early Cretaceous. This set is dominated by river and lake facies “red layer” which is purple and red, mainly fine- siltstone, mudstone, and a small amount of gravel and limestone deposits that is assigned to the Wangshi Group Xingezhuang Formation. Volcanic activity is roughly equivalent to the cyclops of Shiqianzhuang in the region. This study provides a reference for the sedimentary time of the Wangshi Group Singezhuang Formation in Jiaolai basin, and also reveals the characteristics of early Cretaceous volcanic activity in this period, and provides reference for the restoration of the Cretaceous prototype basin and the evolution of paleogeography in Jiaolai basin.