The effect of ZnO content on structure and properties of ZnO-B2O3-SiO2-BaO glass as a research object for copper paste was studied by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), raman spectroscopy (Raman), 27Al nuclear magnetic resonance aluminum spectroscopy (27Al NMR), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The results show that with the increase of ZnO content, the molar ratio of BO/NBO, the average bridge oxygen number and the molar ratio of ［ZnO4］/［ZnO6］ all increases first and then decreases, the molar ratio of ［BO4］/［BO3］ increases, the molar proportion of ［AlO6］ and ［AlO5］ increases and the molar proportion of ［AlO4］ decreases in glass samples, which results in the trend first dense and then loose in the connection degree of network structure of glass samples. Among them, the network structure is the densest when the ZnO content is 36% (mass fraction). With the increase of ZnO content from 32% to 42% (mass fraction), the glass transition temperature Tg, initial sintering temperature TS1 and the coefficient of thermal expansion (CTE) decrease first and then increase, and the CTE value range is 6.0×10-6~6.3×10-6 K-1. It meets the requirements of thermal expansion and sintering temperature for sealing copper paste with Ca1-xSrxZrO3 ceramic substrate.