This　study　is　interested　in　executing　an　optimal　wavelet　transform　(WT)　to　interpret　the　continuous　leak　acoustic　emission　signal　precisely.　Thus,　this　paper　proposes　detailed　guidelines　on　how　to　select　an　optimal　mother　wavelet.　The　recurring　dominant　signal　patterns　were　first　isolated　from　the　raw　leak　AE　signal.　Having　their　correlation　similarity　with　available　standard　mother　wavelets　led　to　the　optimal　choice　of　mother　wavelet.　The　WT　spectrogram　with　mother　wavelet　cmor1-1.5　presents　an　excellent　leak　frequency　band　and　peak　leak　frequency　in　comparison　with　other　mother　wavelets.　Cross-correlation　tests　were　further　carried　out　to　evaluate　the　ability　of　cmor1-1.5　for　locating　the　leak　source　with　WT　coefficients　on　the　leak　characteristic　frequency.　Furthermore,　through　directly　transferring　the　raw　leak　AE　signals　into　the　cross-correlation　function　to　recalculate　their　time　difference　of　arrival　(TDOA),　the　location　results　of　the　leak　source　have　a　huge　deviation　or　are　fundamentally　impossible.　Thus,　comparison　incredibly　indicates　the　significance　of　the　choice　of　suitable　mother　wavelet,　which　also　further　highlights　that　having　an　optimal　choice　of　the　mother　wavelet　in　the　proposed　method　led　to　the　accurate　location　for　the　leak　source.　©　2020　American　Society　of　Civil　Engineers.