The magnetic susceptibility of powderedFeCl2·4H2Ohas been measured between 1.3° and 4.2°K andfrom 14° to 21°K by an ac mutual-inductance method. A maximum, apparently associated with an anti-ferromagnetic-paramagnetictransition, is found near 1.6°K. In the hydrogen region, a Curie-Weiss law isobeyed, the Curie constant yielding a splitting factorg = 2.19for theFe++ion if its effective spin is assumedto beS = 2.