The invention discloses a formula of novel rubber with high stability. The novel rubber is prepared from the following raw materials in parts by weight: 5.3 to 8.6 parts of modified molding powder, 1.5 to 3.6 parts of kaoline, 0.82 to 1.13 parts of semi-reinforcing carbon black N774, 4.6 to 7.8 parts of polymeric borate ester fiber, 0.5 to 1.5 parts of a homogenizing agent, 0.8 to 1.3 parts of tribasic lead sulfate, 0.8 to 1.5 parts of trioctyl trimellitate and 2.6 to 4.3 parts of nitrile rubber. The novel rubber has good high temperature resistance and excellent heat conduction performance, the heat conduction performance of the material can be further improved, and the stability of the material in a high-temperature environment is also improved; the novel rubber has the advantages of reasonable formula, aging resistance and corrosion resistance, so that the service life can be prolonged; and the novel rubber is easy to store and is unlikely to become yellow after curing, and the mechanical properties of the material can also be obviously improved, so that the mechanical strength and sealing performance of products are improved.