Rex Jim Lawson (4 March 1935), known as Cardinal Rex, was a singer, trumpeter and bandleader from New Kalabar, Nigeria.

Rex Jim Lawson was an highly emotional and deep musician, who was known to weep and shed tears while singing his own songs on stage, notably the haunting So ala teme. He became one of the best-known highlife musicians of the 1960s in Africa, when Cardinal and his band dominated Nigeria’s highlife scene.

Lawson died on 18 January 1971 in a car accident at the Urhamigbe corner on thef Asaba-Benin Road while on his way to Warri, Nigeria for a performance. He was 36 years old. After his death, his band continued as the Professional Seagulls. Lawson was married to Chief (Mrs.) Regina Rex Lawson who died in October 2008.