A connection mode using oblique reinforcements between precast bottom plate and cast-in-situ beam was proposed, in order to improve the on-site construction efficiency and the connection performance of the precast bottom plates in composite slabs and cast-in-situ beams. Through the low reversed cyclic loading tests on composite slab and cast-in-situ beam specimens using four different connection modes, the hysteretic behaviors of composite slab and cast-in-situ beam specimens such as crack development and distribution, hysteretic characteristics, skeleton curves, ductility, stiffness degradation and energy dissipation capacity were comparatively analyzed. The influences of four different connection modes using extended steel bars, oblique reinforcements, steel bars laid on the combined surfaces and steel bars in grooves on the hysteretic behaviors of the composite slab and cast-in-situ beam specimens were studied. Results show that the hysteretic behaviors of the specimens using oblique reinforcement connection are basically similar to those of the specimens using conventionally extended steel bar connection. The positive bearing capacity of the specimens using steel bar laid on the combined surfaces is large, while the reverse bearing capacity is small, and the asymmetry of the positive and reverse bearing capacity of the specimens the connection mode is more significant compared to the specimens using the other connection modes other connection methods. The bearing capacity, the ductility and the energy dissipation capacity of the specimens using reinforcing bars in grooves connection are better than those of the specimens using extended steel bars and oblique reinforcements connection. The shear span ratio has less influence on the bearing capacity of the specimens using extended steel bars connection and the specimens using oblique reinforcements connection but has greater influence on the reverse ductility coefficient of the specimens using oblique reinforcements connection.