Device for thawing and/or heating medical products such as bags of plasma or frozen blood or frozen stem cells or the like, comprising a main tank (11) for containing heating liquid, provided with heating means (12A) for heating the liquid contained herein, comprising- a secondary small tank (18) in fluid communication with said main tank (11),- a pouch (19) with floppy walls (19A), inserted in said secondary small tank (18) said pouch (19) being opened upwards for inserting a bag (P) of medical product to be thawed,- an hydraulic circuit (20) comprising a first segment (21) of duct designed to put into fluid communication said main tank (11) with said secondary small tank (18) through pumping means (22), and a second segment (23) for fall of the fluid from said secondary small tank (18) to said main tank (11) said hydraulic circuit (20) being designed to pump liquid from said main tank (11) in said secondary small tank (18) so that said liquid surrounds said pouch (19) at least partially, generating a buoyancy force on the pouch designed to make the floppy walls (19A) of the pouch (19) adhere to the product (P) contained inside it.
