Herein, the effects of phenolic resin addition amount, graphite powder with different particle sizes, and coating pretreatment time on the bending strength and forming accuracy of graphite parts were investigated. The variation law was obtained, and the formation mechanism of graphite additives was revealed. Results show that the bending strength and forming error of graphite parts increase with an increase in the phenolic resin addition amount. Compared with -325, -200, and -150 mesh, when the mass ratio of -100 mesh natural flake graphite powder to phenolic resin powder is 6∶?4, the bending strength of the formed parts is optimal, reaching 1.93 MPa. The coating pretreatment of graphite powder not only helps to improve the mechanical properties of the graphite molded parts, but also reduces the thermal conductivity of the powder, thereby improving the forming accuracy of the molded parts. When the coating time is doubled, the bending strength of the formed parts reaches 2.976 MPa and the relative dimension errors of the X, Y, and Z axes are 8.42%, 8.45%, and 13.05%, respectively. In addition, a porous graphite skeleton with a diamond-like carbon structure can be quickly manufactured, realizing the synergy of strength and precision.