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Optical-resolution photoacoustic microscopy (OR-PAM) has been developed for anatomical, functional, and molecular imaging but usually requires multiple scanning for different contrasts. We present five-wavelength OR-PAM for simultaneous imaging of hemoglobin concentration, oxygen saturation, blood flow speed, and lymphatic vessels in single raster scanning. We develop a five-wavelength pulsed laser via stimulated Raman scattering. The five pulsed wavelengths, i.e., 532, 545, 558, 570, and 620  /  640  nm, are temporally separated by several hundreds of nanoseconds via different optical delays in fiber. Five photoacoustic images at these wavelengths are simultaneously acquired in a single scanning. The 532- and 620  /  640-nm wavelengths are used to image the blood vessels and dye-labeled lymphatic vessels. The blood flow speed is measured by a dual-pulse method. The oxygen …