High-resolution model simulation is considered one of the important methods for studying climate change over the Tibetan Plateau (TP), which is characterized with scarce observations. The High Resolution Model Intercomparison Project (HighResMIP) has been added to the Sixth International Coupled Model Comparison Program (CMIP6), but its simulation performance has not been systematically evaluated over the TP. In this study, we evaluate the ability of CMIP6 HighResMIP models to simulate historical climate over the TP and perform an ensemble projection of the TP climate trend in the near future. The results show that, when compared to lower-resolution simulations, higher-resolution simulations of almost all (two-thirds) models reduce the area-mean bias of annual mean precipitation (surface air temperature). A combined assessment of the Taylor diagram involving indices shows that higher-resolution simulations of about one-third of the models outperform their lower-resolution simulations for both annual mean surface air temperature and precipitation, while higher-resolution simulations of the rest of the models are close to or inferior to their lower-resolution simulations. Multi-model ensemble results outperform individual model results, and their higher-resolution simulation generally outperforms the lower-resolution simulation. Under the SSP5-8.5 scenario, an ensemble of higher-resolution models projects significant warming over the TP during 2021—2040 compared to 1995—2014, with relatively weak warming in the southeastern part. Projected precipitation shows an increasing-decreasing-increasing pattern from north to south. The annual mean surface air temperature will increase by (0.81± 0.91) ℃ and precipitation will increase by (0.05± 0.25) mm/d on average over the TP. These findings are useful for understanding the impact of improved model resolution on climate simulation performance over the TP and the evolution of the TP's climate in a warming future world.