Nacaduba biocellata, the double-spotted line blue, is a butterfly of the family Lycaenidae.

Adult females have a brown upperside, while the males are blue with narrow black margins.

The underside of both sexes is pale brown with light and dark wavy lines.

The larvae feed on the shoots, flowers and buds of various Acacia species, including A. aneura, A. betchei, A. brachybotrya, A. deanei, A. erinaceae, A. irrorata, A. karroo, A. ligulata, A. osswaldii, A. penninervis, A. rigens, A. salicina, A. sclerophylla, A. sowdenii and A. victoriae.

They can have a wide range of colours depending on their host plant, including pink, orange, yellow or green.