The development of maritime and underwater archaeology in the last few decades, provide evidence that enriches our knowledge of ship building, trade, war at sea and other aspects of the maritime past. This new source of information supplements what was previously available to archaeologists and derived exclusively from pictures and classical literature. This article aims at examining the various Hellenistic shipbuilding techniques used specifically in the Mediterranean. The relevant data comes from a number of shipwrecks that were excavated, mostly merchant ships which, with the sole exception of the Marsala warship, are the vessels that mostly survived underwater due to their cargo. The examination of the various parts of these shipwrecks such as the keel or framework, proved that the “shell-first” method was the one followed by the shipwrights of the period. However, some construction variations were identified, such as the “skeleton-first” method which lead us to think that other shipbuilding techniques were not totally unknown. The protecting of the ship’s hull with caulking and lead sheathing were also examined as well as the variety of materials used. The timber used to build vessels was also evaluated according to the type and shape of the wood.