Abstract: A Kirkpatrick Baez mirror imaging system has been designed and installed to measure the beam transverse profile and emittance of SSRF storage ring. The new system could be interchangeable with the original X-pinhole system. Two orthogonal cylindrical mirrors are used to image the dipole source point in the horizontal and vertical directions. Hard X-ray with peak energy of 20.5 keV will be focused at the X-ray scintillator camera. Aberration and point spread function which would cause image blur are evaluated. The system commissioning and optimization have been done. The electron transverse beam size has been measured precisely with horizontal 75.9 μm and vertical 20.2 μm. The system stability is less than 0.1 μm.