A low temperature-resistant and non-asbestos NBR insulation formula named TI506 was preparation by using fire retardant agent containing halogen-Sb,aramid fiber and plasticizer. The effect of content of aramid fiber on erosion perfomance of the insulation was investigated. The effect of content of plasticizer on glass transition temperature( Tg) of NBR insulation was also studied. The results showed that the optimum linearosion rate is 45 μm/ s when the content of aramid fiber pulp is 10 to 15 portions and the content of aramid fiber staple is 4 to 6 portions, and when the content of plasticizer DOS is 10 portions, DBP or ATBC is 20 portions,Tg of the NBR insulation can reach -40℃. In addition, mechanical performance, specific heat capacity and conduction coefficient were tested respectively. The results showed that mechanical and erosion perfomances of the NBR insulation by using aramid fiber are excellent,and it made solid rocket engines endure the condition with the temperature from -40℃ to 60℃.