The Bible attributes the construction of the Ark of the Covenant to Bezalel and his assistants, under Moses’ direction and God’s command.
Biblical attribution
In Exodus, God gives Moses detailed instructions for the Ark while he is on Mount Sinai, but Moses then appoints skilled craftsmen to carry them out. The chief craftsman named is Bezalel son of Uri, of the tribe of Judah, assisted by Oholiab and other gifted artisans from Israel.
Role of Bezalel and others
Bezalel is specifically credited with making the Ark itself from acacia (shittim) wood, overlaying it with gold, and crafting its decorative elements as part of the wider Tabernacle project. Many scholars and traditional Jewish sources therefore say that Bezalel “made” the Ark in the practical sense, while Moses served as the mediator who received and transmitted God’s design.
Summary answer
Putting this together, the Ark was made by Israelite craftsmen, especially Bezalel (with Oholiab and others), following the instructions God gave to Moses. Some passages also speak as if Moses made it, but this is generally understood as referring to his leadership of the project rather than his personally doing the manual work.
