The invention discloses a method for calculating output quantity of a power amplifier by using a Volterra correction model, belonging to the technical field of digital signal processing. The method comprises the following steps of: setting a correction constraint condition; measuring a performance parameter of the power amplifier to determine a correction constraint condition expression; correcting input data of the power amplifier by using the correction constraint expression to obtain a corrected Volterra model; and calculating the output quantity of the power amplifier according to discrete data output by the power amplifier and the corrected Volterra model. The output quantity of the power amplifier is calculated by using the method, so that not only the number of coefficients of the Volterra model is simplified, but also the accuracy for calculating the output quantity of the power amplifier by using the Volterra model is improved.