The invention discloses a mutual coupling correction-based radar array adaptive beamforming method. The method includes the following steps that: a mathematical model of the receiving of Q different direction signals by a uniform circular array of M array elements is established, an expression X<^>(t) of the receiving of Q different direction signals containing noises by the uniform circular array of M array elements and K received signal samples are obtained, and an interference and noise sampling covariance matrix R <~> of a sample matrix XK is calculated; the output power Pout (theta0, phi) of desired signals to be detected of which the incident direction is (theta0, phi) is calculated, C is constructed, and C and the output power Pout (theta0, phi) of the desired signals to be detected of which the incident direction is (theta0, phi) are adopted as optimization equations of a quantity to be solved, and a final optimization equation is obtained; it is determined that the product of C and the ideal steering vector alpha (theta0, phi) of the desired signals to be detected of which the incident direction is (theta0, phi) is equivalent to the product of an M*L-dimensional matrix T corresponding to M elements included in the alpha (theta0, phi) and a mutual coupling vector, and it is determined that the mutual coupling vector is composed of the first L elements in the first row in C; and the solution of c and the solution of C are calculated; and an optimization function is constructed, and a mutual coupling correction-based adaptive beamformer weight vector is calculated.