In the early diagnosis of submucosal tumors, using endoscopy to obtain tactile feedback information can help improve the accuracy of elastic modulus detection of biological tissues, thereby accurately locating blood vessels, determining the health status and type of biological tissues, and improving the quality of treatment. In this paper, a novel micro piezoelectric tactile sensor (PTS, ϕ=2.0 mm) suitable for installation on an endoscope to detect the elastic modulus of biological tissue is designed. This device mainly consists of two components with different stiffness (internal and packaging components) and a polyvinylidene fluoride (PVDF) piezoelectric film. Simultaneously, based on the series spring model and piezoelectric transfer equation, a numerical model for PTS/biological tissue contact sensing has been established, and the sensing law of biological tissue elastic modulus and its energy conversion law of PTS have been deeply analyzed via the Comsol Multiphysics. Meanwhile, a PTS prototype was prepared using a MEMS manufacturing process, and a PTS/biological tissue dynamic load testing platform was conducted to test the soft/hard characteristics of different artificial tumors in the pig stomach for validating the above model. Moreover, the calculation results show that most of the axial load is transmitted by the internal components-copper balls, and the deformation of the PDMS encapsulation layer is minimal when PTS comes into contact with harder biological tissues. On the contrary, the PDMS encapsulation layer undergoes greater deformation when PTS comes into contact with softer biological tissues. The calculation results also indicate that the response voltage (V) and stress (σ) generated in the contact area of the PVDF layer near the internal component (copper ball) are significantly higher than those in the contact area with the packaging layer, which reveals the mechanical-electric field coupling and energy transfer process of PTS. Furthermore, the experimental and computational results confirm that the PTS device, with a 2.0 mm diameter, was successfully installed in the endoscopic biopsy channel. It is noteworthy that the ratio of the response voltage (V1/V2) between the internal and the packaging component is linearly related to the elastic model of biological tissue (Et). when Et increases, V1/V2 increases within 0.2~3.5 MPa, which aligns well with the model calculation results. The above proposed PTS device effectively identifies elastic parameters of tissue, and this measurement method providing a new way for solving the measurement problem of biomechanical information of animal tissue.