Chonecetus is an extinct genus of primitive baleen whale of the family Aetiocetidae that lived in the Oligocene period. Its fossils have been found in Canada, in the northeast Pacific. It was first named by L.S. Russell in 1968, and contains two species, C. sookensis and C. goedertorum (Barnes et al. 1995).Like Aetiocetus, Chonecetus possessed both multicusped teeth and the nutrient foramina required for baleen.