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As an emerging ultra-wide band gap (UWBG) semiconductor, β-Ga2O3 has received wide attention in recent years for its potential application in power electronic and short wavelength optoelectronic devices. However, the synthesis of p-type β-Ga2O3 remains a mystery. Many theoretical studies have been conducted recently to explore possible pathways toward p-type β-Ga2O3. Theoretical studies have suggested the potential of using Zn as a p-type dopant. However, there still lacks an experimental study on the effect of Zn doping on β-Ga2O3. Therefore, this thesis experimentally investigates the Zn doping in β-Ga2O3 thin films using the low-pressure chemical vapor deposition (LPCVD) method.Si-doped β-Ga2O3 thin films and Zn-Si co-doped β-Ga2O3 thin films were successfully synthesized by LPCVD. High room temperature mobility (>100cm2/Vs) was observed on Si-doped samples, indicating good crystal quality and electronic transport properties. By comparing the results of Hall measurement and capacitance-voltage (C-V) measurement, it is suggested that Zn doping is effective to compensate the electron concentration. Under the same growth conditions, the electron concentration of Zn-Si co-doped sample was reduced by 3×1017 cm-3 as compared with Si doped sample. The experiment results suggest that zinc doping has minor effect on the mobility of β-Ga2O3 samples. The photoluminescence (PL) spectrum of the Zn-Si co-doped β-Ga2O3 sample shows an additional peak at ~380 nm (3.26 eV). This peak is likely related to the incorporation of zinc.Using the same method, Zn-doped and unintentionally doped (UID) β-Ga2O3 thin films were also successfully synthesized. CV results support the conclusion that Zn doping is effective to compensate the electron concentration. However, Zn-doped and UID β-Ga2O3 samples cannot be measured by Hall measurement at room temperature due to high resistivity. Therefore, further studies and characterization are still required to understand the role of Zn dopants in β-Ga2O3. The results presented in this thesis demonstrate that the effect of Zn as a dopant in β-Ga2O3, which can provide basis and reference for the subsequent research of p-type β-Ga2O3.