Abstract: A new method for determination of protein was developed. At pH 3.6 Britton\|Robision buffer solution, the interaction between tetra-carboxylic nickel phathlocyanine and proteins yielded strongly enhanced RLS signals at λ=388 nm and the enhanced intensity of RLS was proportional to the concentration of proteins. Based on this, tetra-carboxylic nickel phathlocyanine was used as a probe to determine the total proteins in human serum samples. Under optimal conditions, the linear range is 0.00～1.20 mg/L for BSA、0.00～1.00 mg/L for HSA、0.00～1.00 mg/L for total protein , respectively, with detection limit of 5.97×10^-4 mg/L for BSA、2.90×10^-4 mg/L for HSA、4.76×10^-4 mg/L for total proteins .The method has been applied to determine the total proteins in human serum samples and the results was compared to the coomassie brilliant blue G-250 method with satisfactory results.