Composite grid structures have been widely used in aerospace craft， therefore exploring their mechanical property has significant engineering research value. In order to improve the load carrying efficiency of composite gird structures， a method for improving the fiber morphology based on “broken rib reinforcement” is proposed. Through finite element analysis and test verification， the influence of different proportion of broken ribs on the fiber morphology and the tensile performance of composite grid structure ribs is studied. The established finite element model is used to analyze the tensile failure mechanism of composite grid structures treated with “broken rib reinforcement”. The error between the simulation results and the test results is less than 10%， indicating good consistency. The results indicate that proper treatment of broken ribs during the forming process of composite grid structures can significantly reduce the fiber bending angle at the joint and enhance the tensile performance. Compared with not undergoing broken rib treatment， the tensile ultimate load increases by 24.4% when the proportion of broken rib reinforcement ratios is 30%.