Fluorescence microscopy can visualize the distribution of fluorescent molecules of interest in living tissues with high spatial resolution and high contrast. However, with increasing the observation depth, it becomes difficult to visualize molecules accurately because of light scattering in living tissues. As one of the imaging to improve the observation depth, photoacoustic microscopy (PAM) has been attracting attention. Because the thickness of skin is several mm, PAM is useful to visualize structures in whole skin with high contrast and high spatial resolution. In this paper, we have demonstrated the visualization of blood vessels in mouse ear using PAM with adaptive optics. In addition, we have introduced the combination of PAM and nonlinear optics to improve depth resolution without using high-frequency components of generated photoacoustic waves.