Abstract: To improve the tribological behavior of calcium sulfonate complex grease, the anti-wear and anti-friction performance of grease with ultrafine Ni powder or Ni/Bi composite powders with different load were investigated by four-ball tribological tester. The morphology and component of wear spot were characterized by Scanning Electron Microscope (SEM) and Electronic Differential System (EDS), and the anti-wear and anti-friction mechanism were discussed. The results show that the friction coefficient (μ) and wear scar diameter (WSD) all decrease first and then increase with the increase of the amount of Ni powders. The μ value of composite grease first decrease then increase with the increase of ratio and total amount of Ni/Bi composite powders, while the WSD value has no change. The composite grease achieves the best tribological performance when the Ni amount reaches 2.0% and the ratio of Ni/Bi is 1:2. The value of μ and WSD decrease 34.2% and 4.2%, respectively, compared with basic grease. The test results indicate that anti-friction performance of the calcium sulfonate complex grease with composite powders is improved significantly, while the anti-wear properties change little.