Crassocephalum crepidioides(Benth) S. Moore (Asteraceae) commonly called “thickhead” is underutilised, indigenous to the rainforest of West and Central Africa but has also been introduced and naturalised throughout tropical and sub-tropical Asia, Australia, Tonga and Samoa. The species is an important medicinal and leafy vegetable endemic to the South-western region of Nigeria. Its cultivation, utilisation and local knowledge base could be stronger than the mainstream vegetables. Genetic diversity is uninvestigated for breeding and conservation purposes. The dataset consists of partial rbcL gene sequences, amino acid profiles and nucleotide compositions for 22 accessions ofC. crepidioides.The dataset provides information on the species distribution (Nigeria), genetic diversity and evolution. The sequence information is integral for developing specific DNA markers for breeding and conservation purposes.