A device for the quick heating of fluid material, in particular food, comprises: a container (20) for the fluid material and a heater (12). According to the invention said heater consists of a microwave generator (12), or magnetron, equipped at one end with an antenna (13). Said container (20) comprises a treatment body (21) equipped with at least one recess (24) for the passage of said fluid material to be treated and with a seat (23) for receiving said antenna (13), said recessed treatment body (21) being enclosed in an airtight outer structure (28, 29).