Using the plastic shear deformation of panel zones (PZs) to increase the ductility and seismic energy dissipation of structures is a common practice in most countries specifications. This makes PZs generally yielding before columns and beams, and the shear deformation of PZs is relatively large. In order to explore the elasto-plastic properties of PZs, tests of different types of beam-column connections under monotonic loads were conducted firstly. Focus of tests is to explore the influence factors on elasto-plastic properties of PZs. Then based on test results and existing research data, simplified calculation methods of PZs strength and stiffness in the elastic and elasto-plastic stage were derived, and bilinear relationship expression of PZs moment-rotation was also given. Finally, the simplified calculation method for considering the effects of PZs elasto-plastic shear deformation on story drift of steel frames was presented.