The　scale　modeling　is　widely　used　in　the　study　of　hydrogen　leakage　diffusion,　however　the　similarity　between　the　hydrogen　leakage　scale　modeling　and　the　full-scale　model　remains　incomplete.　This　article　established　a　fullscale　and　a　1/5th　scale　model　and　verify　the　accuracy　relationship　between　the　two　models.　Firstly,　by　comparing　the　full-scale　model　with　only　changing　the　size　simulation,　it　was　found　that　the　accuracy　of　the　two　models　was　poor.　However,　after　using　the　similarity　theory　to　change　the　initial　leakage　conditions,　the　overall　overlap　between　the　full-scale　and　the　scale　modeling　was　improved　apparently.　Under　the　initial　conditions　of　this　study,　the　combustible　cloud　maps　of　the　two　models　that　only　changed　in　size　exhibit　poor　coincidence.　The　results　show　that　the　equivalent　performance　of　a　scale　modeling　instead　of　a　full-scale　model　can　be　greatly　improved　by　using　the　similarity　theory.　The　findings　of　this　study　can　provide　a　valuable　reference　for　experimental　results　based　on　the　scale　models　to　the　full-scale　models.