Objective: Neodymium-doped yttrium aluminum garnet (Nd:YAG) lasers have been used for a wide range of dental applications. However, the safety of their clinical applications is still in question. The aim of the present study was to investigate histopathologic changes in rabbit dental pulp tissue following pulsed Nd: YAG irradiation through normal dental hard tissue. Methods: Specimens from teeth treated with Nd: YAG laser irradiation from two healthy adult New Zealand white rabbits were examined by light microscopy. Each incisor and molar tooth was treated with different irradiation parameters: energy, 100 mJ; frequency, 10, 20, 30, or 40 Hz; power output, 1, 2, 3, or 4W; emission mode, pulsed; time, 0.5 min. Results: Histological investigation revealed that laser irradiation at different power outputs did not damage the pulp tissue. At power output of 4 W, however, a prominent depression in the dentin of the rabbit molar tooth was observed. Conclusion: Nd: YAG laser irradiation at the power outputs of 1-4W did not produce any irreversible tissue damage in the pulp of rabbit teeth.