Electron-microprobe analyses of Russian and Mongolian chevkinite-group minerals from little-known host lithologies, including various metasomatic rocks, quartzolites and an apatite deposit, are presented. The mineral species analysed include chevkinite-(Ce), perrierite-(Ce), polyakovite-(Ce) and Sr- and Zr-rich perrierite-(Ce). Compositional variation in the Sr-rich members of the group is broadly represented by the exchange vector (Fe + Mn + Al + REE) ↔ (Ca + Sr + Ti + Zr). Despite the varied parageneses, the chevkinite-(Ce) compositions are similar to previously published data. Many crystals have strong internal compositional variations, partly produced during primary crystallization and partly during low-temperature hydrothermal alteration.