Senanayake or Senanayaka is a Sinhalese surname. Notable people with the surname include:
Charith Senanayake (born 1962), Sri Lankan cricketerD. S. Senanayake (1884–1952), Ceylonese politicianDudley Senanayake (1911–1973), Ceylonese politicianE. L. Senanayake (born 1920), Sri Lankan politicianEdirisinghe Senanayake (born 1970), Sri Lankan shooterFlorence Senanayake, Ceylonese politicianFredrick Richard Senanayake (1882–1926), Ceylonese lawyer and politicianG. B. Senanayake (1913–1985), Sri Lankan writerMaithripala Senanayake (1916–1998), Ceylonese politicianNimal Senanayake, Sri Lankan physician and academicRichard Gotabhaya Senanayake (1911–1970), Ceylonese politicianRosy Senanayake (born 1958), Sri Lankan activist and politicianRukman Senanayake (born 1948), Sri Lankan politicianSachithra Senanayake (born 1985), Sri Lankan cricketerWasantha Senanayake (born 1973), Sri Lankan politicianWilfred Senanayake (1918–2008), Ceylonese politician