PURPOSE: This study aimed at investigating the role of albumin as a boundary lubricant in the lubrication of the Co-Cr femoral head of artificial hip implants by measuring the tribological parameters of the Co-Cr femoral head with Atomic Force Microscope (AFM) techniques. MATERIALS AND METHODS: Samples were prepared from the main wear region of a Co-Cr femoral head from revision hip surgery. Two types of solutions were prepared as lubricants: PBS (Phosphate Buffered Saline) as a control solution and BSA (Bovine Serum Albumin) as a lubricant at concentrations of 10, 20, 30 and 40 mg/ml in PBS solution. RESULTS: There were statistically significant differences in the frictional coefficients (micron) of a Co-Cr head between the PBS control and all the concentrations of BSA (10, 20, 30, 40 mg/ml) (P<0.001). Similarly, there were statistically significant differences for the micron between the BSA concentrations of 10, 20, 30 and 40 mg/m for all the cases except between the BSA of 30 and 40 mg/ml (P<0.01). CONCLUSION: There exists a maximum protein concentration of BSA to play a role as an effective boundary lubricant through adsorption on the surface of Co-Cr femoral head.