The　24　channels　acoustic　emission　inspection　and　analysis　instrument　developed　by　PAC　was　used　in　manual　arc　welding　process　of　16Mn,　which　was　in　different　strength　of　an　electric　current.　The　AE　signals　was　collected　and　analyzed　by　parameter　analysis　and　frequency　analysis　method,　in　order　to　explore　the　acoustic　emission　characteristics　of　manual　arc　welding　in　different　strength　of　an　electric　current.　The　results　indicated　that　when　the　electric　current　was　greater　than　standard　electric　current,　the　relationship　between　of　the　count,　the　energy　and　the　amplitude　of　the　AE　signals　was　not　significantly　affected,　and　the　total　count　and　total　energy　have　increased　steadily　with　time.　The　amplitude　were　mainly　distributed　in　500　∼　850　dB,　and　the　total　count　and　total　energy　in　two-channel　were　distributed　in　65∼95　dB,　the　frequency　were　mainly　in　45　kHz.　When　the　electric　current　was　less　than　standard　electric　current,　only　the　relationship　between　of　the　total　amplitude　and　the　time　changes,　reaching　1　300∼1　600　dB,　and　the　amplitude　was　much　larger　than　the　standard　value　in　every　moment.