A compact optical-resolution photoacoustic microscopy system is designed with a pulsed laser diode, which has the properties of being low cost, small size, robust and high repetition frequency. Typical photoacoustic images of carbon fiber and blood vessel phantoms are reconstructed clearly. During the experiments, the pulsed laser diode excitation is droved to implement C-mode scanning excitation with three-dimensional translation stage, and the excited photoacoustic signal is captured by a 1-3 composite ultra-bandwidth ultrasonic transducer. The photoacoustic signal-to-noise ratio is recorded of approximate 11 dB, and the lateral resolution of the current system is improved up to 1.5 μm from 500 μm of the first-generation system. The experimental results demonstrate that the proposal method has the potential to be developed as a configuration of inexpensive, real-time, portable, and high-resolution photoacoustic microscopy technique.