The microstructure characteristic parameters of TC11 titanium alloy during different heat treatments were quantitatively investigated, aiming at the lack of quantitative relationship between microstructure characteristic parameters and room temperature tensile properties of TC11 titanium alloy. The content of equiaxed α phase, grain size of equiaxed α phase, thickness of platelet α phase and aspect ratio of platelet α phase at different heat treatment temperatures were quantitatively characterized using image analysis software. Quantitative relationships among heat treatment temperature, quantitative microstructure parameters and room temperature tensile properties were established. And quantitative relationships between quantitative microstructure parameters and room temperature tensile properties were analyzed using a multivariate nonlinear regression model. The results indicate that the microstructure of TC11 titanium alloy depends on the heat treatment regime. For every 10 ℃ increment in solid solution temperature, the content of the equiaxed α phase decreases by about 4.6%. For every 10 ℃ increment in aging temperature, the thickness of platelet α phase increases by about 0.05 μm. Experimental and statistical analyses show that with the decrease in the content of the equiaxed α phase, the strength of TC11 titanium alloy firsthy decreases and then increases, and the plasticity firsthy increases and then decreases. The grain size of the equiaxed α phase has a small effect on the room temperature tensile properties of the alloy. The increase in platelet α phase thickness increases the strength of the alloy. The correlation between alloy plasticity and platelet α phase thickness ia relatively small. With the decrease in the aspect ratio of platelet α phase, the strength of the alloy firstly decreases and then increases, and the plasticity increases. The relationship between microtissue characteristics and room temperature tensile properties conform to the multivariate monlinear regression model.