Thellusson is a given name. Notable people with the name include:
Thomas Thellusson Carter (1808–1901), significant figure in the Victorian Church of EnglandFrederick Thellusson, 4th Baron Rendlesham (1798–1852), British Conservative Party politicianFrederick Thellusson, 5th Baron Rendlesham (1840–1911), British Conservative politicianPeter Thellusson, 1st Baron Rendlesham (1761–1808), British merchant, banker and politicianPeter Thellusson (1737–1797), Swiss businessman and banker who settled in LondonClaud Thomas Thellusson Wood MC (1885–1961), Bishop of Bedford