A MEMS chip (100) includes a silicon substrate layer (110), a first oxidation layer (120) and a first thin film layer (130). The silicon substrate layer includes a front surface (112) for a MEMS process and a rear surface (114), both the front surface and the rear surface being polished surfaces. The first oxidation layer is mainly made of silicon dioxide and is formed on the rear surface of the silicon substrate layer. The first thin film layer is mainly made of silicon nitride and is formed on the surface of the first oxidation layer. In the above MEMS chip, by sequentially laminating a first oxidation layer and a first thin film layer on the rear surface of a silicon substrate layer, the rear surface is effectively protected to prevent the scratch damage in the course of a MEMS process. A manufacturing method for the MEMS chip is also provided.