In this paper, we present a novelty alloptical dualmode photoacoustic and optical coherence tomography (OCT) system. The dualmode imaging system can realize the photoacoustic imaging and by using a single Michelson interferometer, which can obtain the absorption and scattering information of the tissue. The feasibility and capacity of the system was demonstrated with the mimicking experiments. In addition, in vivo experiments were conducted, the experimental results prove that the dualmode photoacoustic and optical coherence tomography system can acquire the microvasculaure and scattering structure image in tissue with high resolution. Furthermore，the dualmode imaging system has been applied in the detection of basal cell carcinoma and acquired some experimental results, which indicate that the dualmode imaging system has great potential to diagnose the skin tumour.