Abstract: A filter-heat exchanger includes a plurality of hollow wires arranged in parallel with a slit of a predetermined width formed between adjacent hollow wires. The hollow wires each have an inlet and an outlet for a heating/cooling fluid whereby the heating/cooling fluid flows through the hollow wires and fluid to be filtered flows through the slits from one side of the parallelly arranged hollow wires to the other side of thereof. The filter-heat exchanger can accomplish filtering and heat exchanging processes simultaneously in a single step.