This　paper　investigates　the　effects　of　explosion　depth　and　water-level　on　the　time　delay　based　on　the　experiments　carried　out　at　Jiemian　reservoir　in　Sanming　of　Fujian　by　Fujian　Earthquake　Agency　in　November　of　2014.　Analyses　on　the　data　from　the　station　YXBM　show　that　under　the　same　water　level,　pressure　pulses　are　affected　by　air-gun　explosion　depth　so　little　that　the　correlation　coefficient　is　high　and　the　time　delay　is　low,　while　those　of　the　bubble　pulses　are　significantly　different.　They　arrive　faster　as　the　explosion　depth　increases.　The　arrival　time　of　bubble　pulses　advances　nearly　80　ms　when　the　explosion　depth　changes　from　8　m　to　30　m,　which　is　quite　consistent　with　the　records　of　the　ocean　bottom　seismometer.　The　time　delay　is　related　to　the　decreasing　of　the　period　of　signals　resulted　from　the　explosion　depth　increasing.　Both　of　the　pressure　pulses　and　bubble　pulses　are　similar　while　stimulated　at　the　same　explosion　depth　of　air-gun　under　different　water　levels.　So　the　explosion　depth　should　be　considered　in　the　future　study　of　exploring　and　monitoring　the　subsurface　structure　and　its　temporal　variations　using　air-gun　active　source.　©　2018,　Acta　Seismologica　Sinica　Press.　All　right　reserved.