To address the controversy regarding the formation age of the Ershi’erzhan Formation sandstone, in the Mohe basin of the northern Da Hinggan Mountains, this study presents results of LA- ICP- MS detrital zircon U- Pb dating in this paper, and discusses its provenance and tectonic setting together with the geochemistry of major and trace elements. The zircon U- Pb dating results show that 132 data are distributed in the following four periods, 508. 3~492. 3 Ma, 486. 9~435. 5 Ma, 278. 3~254. 2 Ma, and 209. 5~178. 1 Ma. It is considered that the age of the Ershi’erzhan Formation should be Middle- Late Jurassic combined with the minimum age (178. 1 Ma) of the zircon and the age of zircon in the east and west of Mohe basin. The geochemical analysis results show that the REE curves of the Ershi’erzhan Formation sandstone are in good agreement with the REE curves of the active continental margin, and are relatively depleted in high field strength elements (Nb and Ta) and large ion lithophile elements (Ba and Sr), and are relatively enriched in high field strength elements (La, Th, Zr and Hf). Based on the analysis of paleocurrent, source rock, zircon dating and trace element characteristics, it is believed that the parent rocks of the Ershi’erzhan Formation sandstone are mainly from the pre- Mesozoic sedimentary metamorphic basement (Xinghuadukou Group, Jiageda Formation, Erguna River Formation, etc.) and the intermediate acid igneous rocks.