One　of　the　primary　goals　in　the　development　of　underwater　wireless　optical　communication　(UWOC)　is　to　extend　the　link　length.　Meanwhile,　the　key　to　increasing　the　link　length　of　UWOC　is　to　decrease　the　attenuation　of　the　optical　signals　underwater.　This　work　demonstrates　that　a　decreased　underwater　attenuation　coefficient　and　improved　communication　performance　can　be　achieved　by　using　a　pulsed　laser.　The　pulsed　blue　laser　used　in　the　experiment　is　a　self-Q-switched　semiconductor　disk　laser,　whose　Q-switching　is　initiated　by　the　nonlinear　Kerr　effect　of　the　multiple　quantum　wells　in　the　active　region　of　the　gain　chip.　The　width　of　the　laser　pulse　is　about　a　few　nanoseconds　and　the　repetition　rate　of　the　output　pulse　train　is　in　the　order　of　tens　of　megahertz.　According　to　the　measurements　of　the　attenuation　coefficients　at　various　concentrations　of　Maalox　solution,　the　pulsed　laser　has　a　significantly　smaller　attenuation　coefficient　than　the　continuous-wave　laser,　and　this　drop　in　attenuation　coefficient　is　particularly　noticeable　in　turbid　water　with　a　higher　concentration　of　Maalox　solution.　The　attenuation　coefficient　of　the　pulsed　laser　was　only　62%　of　the　continuous-wave　laser　at　a　Maalox　concentration　of　2905　mgm(-3).　Subsequent　tests　reveal　that　the　lower　attenuation　coefficient　of　the　pulsed　laser　is　mainly　resulted　from　the　reduced　scattering　it　encounters　underwater,　rather　than　the　ignorable　decrease　in　the　attenuation　coefficient　raised　from　the　water＇s　absorption　of　the　laser.　A　UWOC　system　based　on　the　above　pulsed　laser　has　also　been　built　and　much　better　communication　performance　compared　to　the　continuous-waves　laser　has　been　obtained.　The　bit　error　rate　of　the　UWOC　based　on　the　pulsed　laser　is　1-2　orders　of　magnitude　lower　than　that　of　the　UWOC　with　a　continuous-wave　laser　when　the　data　rate　is　10　Mb/s　and　the　link　length　is　18　m.