Based on the background of Hubei Yichang Three Gorges Reservoir of Majiagou Jurassic red sandstone, the influence of point load strength IS(50) of common specimens with different shapes (cylindrical, cubical, irregular block) in the point load tests was studied. The results show that for different shapes of specimens, the proper shape correction index m is determined, and the effect of shape effect on the point load strength IS(50) can be neglected. At the same time, the influence of different norms m values at home and abroad is compared..After comprehensive analysis, it is recommended that the correction index m of the red sandstone standard sample in the region is 0.5, and the correction index m of the non-standard sample is 0.42; Combined with the test results of indoor uniaxial compressive strength of red sandstone, the empirical conversion relationship between the load strength IS (50) and the uniaxial compressive strength(UCS)of red sandstone in this area is obtained.