Aluminum nanoparticles were added into pentaerythritol tetranitrate (PETN) to decrease the near-infrared (NIR) laser initiation power. The effects of Al nanoparticles on the minimum power of all fire were investigated under 1064 nm laser initiation. The initiation mechanism was studied using differential scanning calorimetry, reflectance spectroscopy, laser-induced breakdown spectroscopy, and shadowgraph technique. Results showed that the addition of Al nanoparticles could prominently decrease the minimum power of all fire of PETN. The PETN doped with 0.5 % Al nanoparticles could be reliably initiated with 40 mJ laser energy (1064 nm, 14 ns). However, the increase in Al nanoparticles increased the minimum power of all fire. A thermal mechanism could be affirmed for the initiation of PETN doped with Al nanoparticles with the NIR laser initiation. First, Al nanoparticles were heated to high temperature to form hotspots by absorbing input NIR laser energy. Then, the PETN surrounded by the hotspots propagated self-sustaining chemical reactions and exploded. With the increase of Al nanoparticles, the increase in thermal conductivity and the decrease of the hot-spots temperature resulted in high laser power to initiate explosives.