船主(Ship's Master或者Shipmaster)或者船長(Captain)係嚮度,指揮隻點行嘅人。佢通常係指揮手下船員做嘢,唔係親自駕船(駕讀揸)。

甲板上,佢下便重有大副(Chief Officer),二副(Second Officer)咁。車房大偈(Chief Engineer)添。

船主同火長有啲分別。船主係拎到船主牌嘅人,而火長係船東委任揸船個位。