Rex Jim Lawson (c.1930 - 1969), known as Cardinal Rex, was a singer, trumpeter and bandleader from Kalabari (Ijaw), Nigeria. One of the best-known highlife musicians of the 1960s, Lawson played with Sammy Obot, Bobby Benson, Victor Olaiya, Chris Ajiko, and other Ghanaian and Nigerian musicians and bands. His greatest success came as the leader of the Mayors Dance Band; their recorded hits include So ala teme, Yellow Sisi, Gowon Special, and Jolly Papa. His most popular hit is probably Love Adure, which is still a sure floor-filler in Nigeria to this day.

A highly emotional and deep musician, Lawson was known to weep and shed tears while singing his own songs, notably the haunting So ala teme. Sir Maliki Showman, the famous Nigerian tenor saxophonist who played with Bobby Benson, Victor Uwaifo and Rex Lawson, remembers Lawson as always placing music over money. Lawson is famed for his infectious gregariousness, his musical vision, talent, perseverance and individuality. Lawson died tragically in 1971 in a car accident on his way to play a show in Warri, Nigeria.

His music is loved to this day in Nigeria. His songs are regularly performed and danced at live band shows in Nigeria, and a number of young musicians have resang some of his old hits, and his relevance continues to be felt. The young new generation highlife musician CHE & the Continuous Highlife Evolution, for instance, dedicated his hit debut album PALMGROOVE to Rex Lawson.