A system is provided for photodynamic diagnosis and therapy of skin diseases. In particular, a camera head is provided to irradiate a white light, a fluorescent excitation light and a therapeutic light for the photodynamic therapy from the inside of a case onto the skin region being in contact with a view hole. Additionally, a digital color TV camera collects the light from the skin region and outputs a generated image signal. In particular, an image processing and analysis system receives the image signals from the camera head to process, analyze and store the same, displays a color image by the white light, a fluorescent image by the excitation light and the therapeutic light for the photodynamic therapy, obtained by the digital color TV camera, and a synthesized image thereof, and controls the general operations of the camera and the light source system.