The extrusion press frame deformation has direct influence on quality of extruded product. The frame solid model including front beam, rear beam, pretensioned columns, and compressed columns was established by using software SolidWorks for 36 MN prestress structure extrusion press, then it was imported into software MSC.Marc, and transformed into finite element model. With a direct loading method applied to the frame preloading, the loaddeformation of the frame under preload and working load was analyzed, and the frame deformation contours and compressed columns deformation rules were obtained. The results show that the compressed column deformation direction is outer convex under preload, on the contrary it is inner concave under working load;  uncentrosymmetric front beam will result in that the upper compressed column deformation is a little larger than lower. These research results provide reference for design and application of extrusion press.