The present invention provides a concentration device and a concentration method that can produce a concentrate that has a prescribed concentration factor stably and at low cost. A concentration device (1) that comprises: a membrane distillation cell (10) that has a first chamber (10a) in which a stock solution flows and a second chamber (10b) that is separated from the first chamber (10a) by a porous membrane (11) that selectively transmits steam a heater (20) that heats the stock solution a cooler (40) that cools the second chamber (10b) a pressure adjustment device (70) that changes the pressure of the first chamber (10a) or the second chamber (10b) and thereby adjusts the pressure difference between the first chamber (10a) and the second chamber (10b) and a control unit (80). The control unit (80) controls the heater (20) and the cooler (40) to a prescribed temperature range and controls the pressure adjustment device (70) such that the volume of a condensate in the second chamber (10b) is a prescribed volume. A concentration method wherein, in a membrane distillation cell, the temperatures of a first-chamber side and a second-chamber side of a porous membrane are adjusted to a prescribed temperature difference and the pressure difference between a first chamber and a second chamber is adjusted such that the volume of a condensate is a prescribed volume.Linvention concerne un dispositif de concentration et un procédé de concentration pouvant produire un concentré qui présente un facteur de concentration prescrit de manière stable et à faible coût. Un dispositif de concentration (1) comprend : une cellule de distillation à membrane (10) possédant une première chambre (10a) dans laquelle sécoule une solution mère et une seconde chambre (10b) séparée de la première chambre (10a) par une membrane poreuse (11) qui transmet sélectivement de la vapeur un dispositif de chauffage (20) qui chauffe la solution mère un refroidisseur (40) qui refroidit la seconde chambre (
