In order to overcome the energy density limitations of lithium-ion batteries consisting of graphite anodes, studies on lithium metal batteries (LMBs) have been actively conducted. However, most LMBs related studies focus on suppressing the growth of unpredictable dendrites. Research for production processes has been rarely conducted. In the paper, laser processing is introduced to improve the drawback of conventional processing for Li metal. Moreover, a low humidity maintenance chamber is manufactured to prevent oxidation of Li metal during laser processing because Li metal easily reacts with moisture. The chamber has a closed space that does not allow outside air to enter, and a glass that allows the laser beam to pass through is installed at the upper part. In addition, silica gel is installed to maintain low relative humidity. The dew point inside the chamber drops to -17.4 ℃ in 1 hour. This result implies that the chamber can prevent Li metal oxidation. Next, we analyze the effect of transparent plate glass on laser beam with Gaussian distribution. Finally, it is confirmed through experiments that lithium metal is not contaminated by moisture during laser processing using a manufactured chamber.