Abstract: With the vigorous development of renewable energy, solar cells have received more and more attention. Based on SCAPS-1D solar cell simulation software, a new solid-state dye-sensitized solar cell (ss-DSSC) with kesterite compound CZTS (Cu-Zinc-tin sulfide) as the hole transport layer was studied. A ss-DSSC cell with FTO/TiO₂/N719/CZTS/Au as the model was established, and two interface defect layers were introduced. The results show that the photoelectric conversion efficiency is 12.83%, the open circuit voltage is 0.768 V, the short circuit current density is 23.23 mA/cm² and the filling factor is 71.93%. Then, the influences of electron and hole transport layer thickness, the electron affinity of CZTS, dye layer thickness, defect density, doping concentration, and defect density of two interfacial defect layers on four key performance parameters of ss-DSSC (photoelectric conversion efficiency, open circuit voltage, short circuit current density, filling factor) and energy band diagram were analyzed, and the optimal parameters were determined. The results after optimization and before optimization were compared, it was found that the battery performance was significantly improved, and the optimized PCE was 16.06%, Voc was 0.851 V, Jsc was 23.93 mA/cm², FF was 78.82%, and the capacitance-voltage characteristics of ss-DSSC were analyzed, the results is consistent with the simulation.