A folding unit for producing sealed packages of pourable food products from respective packs, each having a main portion folded into a desired shape, and opposite end portions to be folded to form respective folded ends of a relative finished package. The unit has a first folding station, in turn having a first retaining mechanism for securing each pack by a relative first end portion, and a first folding mechanism for folding a relative second end portion of the pack. The unit also has a second folding station located downstream from the first folding station in the traveling direction of the packs, a second retaining mechanism for securing each pack by the relative folded second end portion, and a second folding mechanism for folding the relative first end portion.