Abstract: This paper reports that the content of coenzyme Q₁₀ injection can be directly determined by orthogonal function spectrophotometry. In alcohol, using the 3-point quadratic polynomial in the wavelength range 286 to 292 nm at 12 nm intervals, the coefficient of the polynomial, P₂, provides a precise estimate for coenzyme Q₁₀ and eliminates the interference from TW-80. The mean recovery of coenzyme Q₁₀ is 98.60.66%. This method is simple and the results obtained are satisfactory both in recovery and in precision.