In the last 20 years, x-ray imaging technology has developed to meet the needs of x-ray photoetching, spatial exploration, high-energy physics, and diagnosis of inertial confinement fusion. Because conventional imaging methods are not suitable in the x-ray range, grazing reflective imaging and coded aperture imaging methods have been adopted. In this paper, we describe the design of a noncoaxial grazing incidence KBA microscope. The microscope consists of two sets of spherical mirrors that scatter in orthogonal planes. An optical ray tracing program is used to analyze and evaluate the theoretical aberrations of the microscope. This allows us to optimize the x-ray imaging system. The analytical results provide a reliable foundation for determining the useful range and the manufacturing and assembly tolerances of the microscope.