Graphene with atomic thickness has advantages of excellent electromechanical properties and super-large specific surface area. Combined with the significant piezoresistive effect, graphene opens up window for next generation of the ultra-sensitive pressure sensor. The main cause of the low-yield for graphene sensor made by the conventional fabrication process is analyzed to be the overloaded stress during its release process from the liquid. To solve this problem and improve the yield, a new pressure sensor scheme by using polymethylmethacrylate (PMMA) / graphene composite heterogeneous film (hetero-film) is proposed to replace the atomic graphene film. The corresponding fabrication process compatible with the traditional COMS process is designed and applied to sensor fabrication, which reaches a much higher yield and holds the hope for large-scale fabrication. The pressure sensing test shows that the sensitivity of the new graphene pressure sensor is up to 7. 42 × 10 -5 / kPa, which is comparable to the existing research. However, the extracted sensing precision is low to 2. 6% ~ 3. 5% in the full-scale range (FS), which is nearly 2 orders worse than the silicon-based high-performance pressure sensor (0. 05% ~ 0. 01% FS). The electrical noise of the measurement system and the intrinsic resistance noise of the polluted graphene may be the key root. This work suggests that more research on graphene pressure sensor should focus on the improvement of sensing precision indicator rather than the pursuit of sensitivity.