With the aim of enhancing the flowability of the ABS resin, the effect of N, N'-ethylene bis oleamide (EBO) as a new lubricant on the melt flow rate (MFR), torque value, and rheological behavior of ABS resin was investigated. The result showed the MFR of the ABS resin with 2.0 wt% EBO was 22.1 g/10 min, which was improved by 49% compared with the pure ABS resin (14.8 g/10 min). The torque value of the ABS resin, including 2.0 wt% EBO (1.69 N·m) was lower than that of the pure ABS resin (2.03 N·m). The rheological study further indicated that EBO can reduce the complex viscosity of the ABS resin. The above results indicated that EBO was an effective lubricant for the ABS resin. A possible lubrication mechanism was proposed based on the consequences of the rotational rheometry, dynamic mechanical analysis (DMA), and molecular dynamics simulation (MD). EBO decreased the entanglement density of the SAN molecular chains and increased the mobility of the SAN molecular chain segments. On the other hand, EBO increased the space for the free migration of the SAN molecular chain fragments due to the free volume effect. This work, we suggest, will provide a fresh avenue to achieve high-flow ABS resin and new insights into the lubrication mechanism of lubricant in the ABS resin.