The Cronulla-Sutherland District Rugby Football League (Cronulla-Sutherland District Junior Rugby Football League in the case of junior football) is an amateur competition for rugby league clubs in and around the Sutherland Shire district of Sydney, New South Wales, Australia.

The Cronulla-Sutherland District Rugby Football League was formed in the early 1950s following the formation of several new Sutherland Shire based clubs and the arrangement of a committee that would eventually become the CSDRFL.

All Shire based clubs had previously played in several Inter-District matches throughout the year but with the formation of a localised Sutherland league these were no longer deemed necessary.

The Cronulla-Sutherland Junior District Rugby Football League was formed in 1963 after a general meeting among several of the already established junior clubs whom decided it would be beneficial to form and arrange an annual competition amongst themselves and other teams in the Sutherland Shire.

Southern Open Age (previously known as Cronulla A-Grade) is the premier rugby league competition clubs in the Cronulla-Sutherland and St. George districts of Sydney.