Hypopharyngeal cancer often coexists with other primary cancers, particularly esophageal cancer. Making a treatment choice for patients with synchronous double cancer may be difficult, and the treatment may not be performed as scheduled. We examined 152 patients with hypopharyngeal cancer receiving first-line therapy in our hospital from January 2011 to December 2014. Eighty-four patients had double cancer （55％）, and the most common second malignancy was esophageal cancer, which showed both synchronous and metachronous associations. The 5-year overall survival （OS） of patients with hypopharyngeal cancer alone （n＝68） and that of those with hypopharyngeal and esophageal cancers （n＝52） were 54％ and 80％, respectively, with a significantly better survival in patients with double cancer. This was presumably because of the early detection of hypopharyngeal cancer using upper endoscopy in patients with double cancer. Regarding synchronous double cancer comprising hypopharyngeal and esophageal cancers, the OS rates were 100％, 65％, 75％, and 56％ for patients with early-stage hypopharyngeal and esophageal cancers, advanced hypopharyngeal and esophageal cancers, early-stage hypopharyngeal and advanced esophageal cancers, and advanced hypopharyngeal and early-stage esophageal cancers, respectively. Early-stage esophageal cancer cannot be treated early, and chemotherapy may be administered as a first-line treatment. Even if early-stage hypopharyngeal cancer responds to previous chemotherapy, a close follow-up or treatment is required.