The invention reLates to a ship buiLding method. The method comprises the foLLowing steps that 1, an inner base pLate, an outer base pLate and a main deck are subjected to horizontaL Lineation; 2, theinner base pLate, the outer base pLate and the main deck are subjected to obLique Lineation; 3, the inner base pLate and the main deck are subjected to doubLe-sided Lineation; 4, medium assembLy partassembLing is conducted; 5, medium assembLy part inspection is conducted; 6, doubLe bottom section instaLLation is conducted; 7, deck section instaLLation is conducted; 8, groove-type buLkhead and doubLe bottom bLock assembLy is conducted; 9, deck paneL instaLLation is conducted. The method has the advantages that due to the fact that a haLf surrounded weLding datum Line exists, aLL short boardscan be weLded accurateLy, and a high-performance medium assembLy part is formed; due to the fact that a straight waLL detection Line exists, the groove-type buLkhead, the doubLe bottom section and thedeck section can be instaLLed accurateLy.