The invention provides a method for removing cracks of Rene104 nickel-based superalloy during laser additive manufacturing, and belongs to the fields of additive manufacturing and superalloy. Aiming at solving the problem that cracks are liable to occur to Rene104 nickel-based superalloy with a high Al content and a high Ti content (Al+Ti>5%) during laser additive manufacturing, by designing laserforming parameters and sub-regional scanning strategies, generation of large-size cracks in a formed part is suppressed; then stress relief annealing is used for completely removing residual stress in the formed part; and discharge plasma sintering treatment is adopted for removing the cracks in the formed part, and grain growth during the sintering process is suppressed. The scheme that after the formed part is obtained through laser additive manufacturing, in combination with stress relief annealing and discharge plasma sintering treatment, the cracks in the formed part are removed is proposed for the first time. By using the method for preparing the Rene104 nickel-based superalloy with the high Al content and high Ti content, no cracks are found in the formed part, and the tensile strength of the formed part at the room temperature can reach 1300 MPa or higher.