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Zirconium alloys are used as cladding materials for fuel components in reactors due to their excellent mechanical properties, excellent corrosion resistance and low thermal neutron absorption cross-section. However, Zr-4 can no longer reach the requirements of nuclear power technology under higher burn-up conditions. Therefore, it is of great significance to develop new zirconium alloys by regulating the alloy composition. In this study, Zr-4 and two other new zirconium alloy materials were subjected to conventional tensile tests at room temperature and 315℃. The precipitation phase changes caused by composition differences were analyzed based on the calculation results. And the importance of precipitation strengthening mechanism was proposed for the performance improvement of zirconium alloys. The mechanical properties of zirconium alloy were tested for the first time by using small punch test. The coefficient values related to the zirconium alloy material itself were determined in the empirical formula between the conventional tensile test and the small punch test. The feasibility of the small punch test for the evaluation of the tensile properties of zirconium alloys was verified. Zr-4 and two other new zirconium alloys were hydrogen-charged at 400°C by gaseous hydrogen permeation, and their mechanical properties were tested by SPT. The results show that the hydrogen-charged Zr alloys have a special phenomenon of "platform region" in the plastic instability stage of the load-displacement curve. In this paper, the morphological characteristics of hydrides were characterized by metallographic analysis and their contents was quantitatively estimated. It was speculated that the difference in the fracture toughness between hydrides and matrix, the special long chain configuration of the hydride phase and its strong orientation have an important correlation with this phenomenon.