The invention discloses a Coude optical path adjustment method based on double theodolites. A Coude optical path is disposed on a rotary table, and the adjustment method comprises the following steps:(1), installing a first reflector and an auxiliary plane reflector, placing the first theodolite, and adjusting the theodolite so as to enable a received cross hair image to coincide with a cross hair of the first theodolite; (2), removing the auxiliary plane reflector, placing a second reflector and the second theodolite, adjusting the second theodolite so as to enable a received cross hair image to coincide with a cross hair of the second theodolite and enable the received cross hair image not to rotate with the rotary table; (3), installing a fourth reflector, placing a third reflector, removing the second theodolite, and adjusting the second theodolite so as to enable the received cross hair image to coincide with the cross hair of the second theodolite and enable the received cross hair image not to rotate with the rotary table. Through the improvement of the overall step and flow setting of an adjustment method, the method provided by the invention can effectively solve a problem of high-precision alignment of all plane reflectors in the adjustment of the Coude optical path.