The invention provides a single-joint fault space manipulator pose reaching space solving method for realizing quantitative analysis of space manipulator reaching pose degradation conditions after locking of any joint faults. The method comprises the following steps: the manual limiting solution is performed on space manipulator degradation working space locked by single-joint faults based on joints; gesture reaching degree indexes are built to solve space manipulator anticipant gestures facing tasks; the anticipant gestures and all scattering coordinates in the degradation working space are synthesized to build manipulator terminal pose sets; and poses with inverse solutions are screened to obtain the space manipulator pose reaching space with single joint faults. The method can realize solution of the space manipulator pose reaching space locked by any joint faults.