The traditional three-dimensional guidance law generally divides three-dimensional space into vertical plane and horizontal plane respectively, which may lead to the lack of coupling information. It also doesn′t take heat flux of infrared seeker and constraint of terminal velocity into account. To solve this problem, a guidance law based on the missile of adjustable thrust was proposed in the instantaneous rotary line-of-sight plane of rotary line-of-sight frame. The acceleration instruction in the direction of perpendicular to line-of-sight was designed to satisfy the criterion of motion camouflage strategy. Meanwhile, an overload instruction in the direction of line-of-sight was built with variable weighted change rate of heat flux limit and ideal overload which can satisfy the constraint of terminal velocity. Simulation results demonstrate that the designed guidance law has a good performance with the heat flux limit of infrared seeker, constraint of terminal velocity and available axial overload limit when attacking the high maneuvering target and initial misalignments of infrared seeker exists. The rate of line-of-sight is under 3 ( °)/s, so it has certain engineering application value.