Kashin kuboid ƙashi ne na kwalta da ke cikin ƙafar ƙafa, a wajen waje na tsakiyar ƙafar, tsakanin ƙashin (ƙashin diddige) da metatarsal na huɗu da na biyar (kasusuwan ƙafar ƙafar gaba). An siffata shi kamar cube, don haka sunan "cuboid". Kashin kuboid yana daya daga cikin kasusuwan tarsal guda bakwai kuma yana taka muhimmiyar rawa wajen samun natsuwa da sassaucin kafa.
