The basking shark (Cetorhinus maximus) is the world’s second largest fish and the subject of strong conservation concern. Minimal genetic assessment exists for this globally distributed but regionally endangered species. We describe the complete mitochondrial genome sequence of C. maximus, obtained via polymerase chain reaction-based Sanger sequencing. The total length of the mitogenome is 16,670 bp and consists of 2 rRNAs, 22 tRNAs and 13 protein-coding genes. The base composition has an A + T bias (63.6%), as is often seen in other sharks. Gene order is equivalent to that found in most vertebrates.