For the large-angle attitude maneuver of spacecraft under complex constraints, a efficient maneuver path planning for attitude and time scaling method on 3-dimensional special orthogonal group was proposed. Aiming at handling the attitude constraints during maneuvering, a gradient-based obstacle avoidance methodology was designed and the attitude routes and desired angular velocity trajectory was obtained on the virtual time domain. Considering the maximum output torque of the actuator, an iterative nonlinear time scaling method was proposed to adjust the angular velocity/control torque. Simulation results show that the proposed method not only satisfies the attitude constraints and the control torque constraints during the spacecraft maneuver process, but also significantly shortens the maneuver time comparing with existing methods. Novel results provide a new insight for efficient constrained attitude planning and controller design.