Abstract: The prefabricated shear wall integrated with reinforcement and formwork (IRF) is light in weight and easy to transport and install. A new IRF shear wall was constructed by eliminating the concrete protector between the reinforcement and the formwork to reduce the thickness. In order to study the effects of roughness of combined interface and boundary elements’ longitudinal reinforcement ratio on the mechanical performance of IRF shear wall, the pseudo-static tests of one RC shear wall and three IRF shear walls under a constant axial force were conducted. The results show that all specimens fail in flexural failure modes, and the crack distribution area of RC shear wall is larger and more densely than that of IRF shear wall; the failure mode of IRF shear wall are similar to RC wall and the bearing capacity is greater than RC shear wall; the displacement ductility of IRF shear wall is greater than 4.5, the cracking displacement angle is much larger than 1/1000, and the ultimate displacement angle is greater than 1/120, indicating good seismic performance, which can satisfy the requirements of “equivalent cast-in-place”. Increasing the roughness of combined interface can delay cracking and enhance the integrity, while increasing the reinforcement ratio of boundary element can improve the bearing capacity; when the IRF specimens fail, the ratio of slip at the horizontal joints to the horizontal displacement at the loading point is less than 1.8%, thus the horizontal joint is reliable. Based on the plane section assumption and considering the difference in stress-strain curves of concrete and mortar, the formula for calculating the flexural capacity of normal section of IRF shear wall was established. The equivalent rectangular stress diagram method was used to simplify the calculation formula, and the equivalent rectangular stress diagram coefficient was calculated according to the standard value of the compressive strength of mortar. The results show that the test value is 1.13~1.14 times the calculated value, which can be used to calculate the flexural capacity of normal section of IRF shear wall.