Carbon fiber/epoxy resin (CF/EP) composites exhibit low interlaminar fracture toughness perpendicular to the fibers, making them susceptible to interlaminar delamination, which significantly impacts the load-bearing capacity and lifespan of the composites. Here, a silicon polymer (Psol) was modified with graphene oxide (GO) to form Psol/GO for improving carbon fiber/epoxy resin composites. A systematic study was conducted on how Psol/GO affects the mechanical properties of carbon fiber/epoxy composites. The findings indicate that Psol and GO can work together to enhance the toughness and strength of carbon fiber/epoxy resin. The interlaminar shear strength (ILSS), flexural strength, tensile strength, and impact strength of the Psol/GO/CF/EP composite material have been enhanced to 68.22 MPa, 817.24 MPa, 690.95 MPa, and 95.71 kJ/m2, respectively. When compared with the pure CF/EP composite material, these properties show improvements of 13.32%, 14.26%, 13.51%, and 17.54%, respectively. The DMA results indicate that the storage modulus (E') of carbon fiber/epoxy resin composites with Psol/GO was decreased to some extent. Furthermore, when the ratio of Psol to GO is 0:0.1, the glass transition temperature (Tg) of the composite exhibits a slight increase. In comparison to the pure CF/EP composites, Tg was increased from 80.9 degrees C to 82.9 degrees C. Psol/GO has better toughening carbon fiber/epoxy resin while increasing its strength. This study provides an effective method for strengthening and toughening carbon fiber/epoxy resin.