The invention discloses a transformer state evaluation method with influence of direct-current magnetic bias taken into account. The method includes the steps that data acquisition is carried out on the state of a transformer; acquired data are classified and processed to serve as the basis for transformer state evaluation; the state of the transformer is evaluated; a comprehensive state evaluation quantitative evaluation system of the transformer is established; the weight coefficient of each one-way state quantity is worked out; the state of the transformer is evaluated by adopting a one-way state quantity scoring function and a ranking membership function through a historical training database to obtain a transformer basic state score; the values of transformer loss and oil temperature rise caused by direct-current magnetic bias are calculated and substituted into the scoring function to obtain a score of the influence of direct-current magnetic bias on the state of the transformer; the arithmetic mean of the two scores is calculated to obtain a transformer health state score with the influence of direct-current magnetic bias taken into account. According to the method, a system comprehensive analysis method is adopted to quantize the influence of direct-current magnetic bias on the state of the transformer, and the real operating state and health level of the transformer under the influence of direct-current magnetic bias can be accurately reflected.