This article primarily compares the microstructure, physical and mechanical properties, and processing performance of ANBR3305, a cold-process soft polybutadiene rubber with medium acrylonitrile content from Lanzhou Petrochemical Company, and NBR40H, a hot-process hard polybutadiene rubber with high acrylonitrile and gel content. The results indicate that ANBR3305 exhibits superior oil resistance, low-temperature performance, and good heat resistance, while maintaining a balance between cold resistance and oil resistance. Its heat resistance can be further studied for applications in general sealing and hose products. NBR40H demonstrates good mechanical properties at room temperature, possibly due to its high gel content, which benefits its mechanical properties at room temperature. It also exhibits good oil resistance, but poor cold resistance and elasticity. Its comprehensive performance can be further studied for applications in harsh environments such as oil.