The intrinsic life limiting factor for a HgBr laser is the chemical reactions of laser gases with the tube materials used. An experimental chemical compatibility study incorporated with the thermochemical calculations was conducted. Glasses, quartz, and ceramics are inert to HgBr2, HgBr, Hg, and Br2; thus they can be used as HgBr laser tubes or insulator materials. Polyimide organics are also unaffected by HgBr when shielded from UV radiation and the discharge. For metals, both thermodynamic calculations and chemical compatibility experiments indicate that only noble metals such as gold and platinum are suitable for HgBr lasers.