Abstract: An in-chamber, mini X-ray imager employing a pinhole and a logarithmic spiral crystal has been manufactured to obtain the K-shell emission monochromatic X-ray images. The imager was tested on the Yang accelerator and successfully obtained the hydrogenlike line and heliumlike line images of the imploding Al wire array. The results show that the imager has excellent monochromacity (the energy band width is less than 1 eV) and is very suitable for acquiring the characteristic X-ray emission images of the medium or low Z imploding Z-pinch loads.