'AJ' was the designation of Allied convoys (together with a numerical suffix) plying the route from Aden to Colombo, Ceylon, and as such reciprocals of the 'JA' series (January 1942/February 1945).

The first of the 13 convoys of this series, some of whose designations were used two or three times, was AJ.1 of 23 January/1 February 1942 with the 10,902-ton British City of Paris carrying 1,375 Mobile Naval Base Defence Organisation troops, 10,926-ton British Eastern Prince and 8,131-ton British Yoma, and the last of the series was AJ.8 of 16/21 February 1945 with the 17,702-ton British Reina del Pacifico.