Joseph O'Mara (16 July 1864 – 5 August 1927) was an Irish opera singer of the Victorian and Edwardian eras. After studying opera in Milan, Italy, he made his London stage debut in 1891 in the tenor title role of the opera Ivanhoe by Arthur Sullivan and soon appeared in other operas. In 1894 he first appeared at Covent Garden Theatre. For three years, he was the principal tenor at Theatre Royal, Drury Lane, also appearing in the pantomime there and elsewhere. In 1896, he created the tenor lead, Mike Murphy, in Charles Villiers Stanford's opera Shamus O'Brien, also playing the role on tour and in America.