Based on nine years (from 2008 to 2016) of monitoring data of net primary productivity (NPP) and climatic factors at Haibei Station, the interannual NPP dynamics of alpine Kobresia pygmaea meadow and alpine Potentilla fruticosa shrubs were analyzed. In addition, the effects of climatic factors on NPP and the characteristics of root turnover across different soil layers were also assessed. The results showed that (1) on an interannual scale, the aboveground net primary productivity (ANPP) of Kobresia pygmaea meadow showed a significant increasing trend (7.02 g m^-2 a^-1), but the ANPP of Potentilla fruticosa shrubs remained relatively stable. Both belowground net primary productivity (BNPP) and total net primary productivity (NPP) of the two vegetation types showed a slight increase (P>0.05). The average ANPP, BNPP, and NPP for the Kobresia pygmaea meadow were (217.55±9.95) g/m², (1882.75±161.33) g/m² and (2100.30±163.38) g/m², respectively. The average ANPP, BNPP, and NPP for Potentilla fruticosa shrubs were (256.27 ±11.4) g/m², (1614.31 ±173.03) g/m², and (1870.58±177.93) g/m², respectively. (2) The ANPP of the vegetation types responded differently to climatic factors. The mean annual air temperature had a significant effect on ANPP for Potentilla fruticosa shrubs, but no significant impact on the ANPP of Kobresia pygmaea meadow. Furthermore, precipitation was not a key factor limiting the NPP of grassland in alpine ecosystems; temperature exerted a stronger effect on the ANPP of alpine ecosystems compared with precipitation. (3) The mean annual air temperature and mean annual precipitation showed no notable effect on the BNPP, indicating that the BNPP was less affected by external climatic factors than the ANPP. (4) Root turnover increased with soil depth and the root turnover of Potentilla fruticosa shrubs was higher than that of Kobresia pygmaea meadow. Our study implies that the ANPP of Potentilla fruticosa shrubs will increase with climate change, but no significant change is expected for the ANPP of Kobresia pygmaea meadow.