We performed multiwavelength photoacoustic (PA) measurement for extensive deep dermal burns in rats to monitor the healing process of the wounds. The PA signal peak at , an isosbestic point for oxyhemoglobin and deoxyhemoglobin (HHb), was found to shift to a shallower region of the injured skin tissue with the elapse of time. The results of histological analysis showed that the shift of the PA signal reflected angiogenesis in the wounds. Until postburn, PA signal amplitude generally increased at all wavelengths. We speculate that this increase in amplitude is associated with dilation of blood vessels within healthy tissue under the injured tissue layer and increased hematocrit value due to development of edema. From postburn, the PA signal showed wavelength-dependent behaviors; signal amplitudes at 532, 556, and continued to increase, while amplitude at , an HHb absorption-dominant wavelength, decreased. This seems to reflect change from shock phase to hyperdynamic state in the rat; in the hyperdynamic state, cardiac output and oxygen consumption increased considerably. These findings show that multiwavelength PA measurement would be useful for monitoring recovery of perfusion and change in local hemodynamics in the healing process of burns.