Pomacentrus flavioculus n. sp. is described on the basis of 140 specimens, 17.1–86.8 mm SL, from Fiji and Tonga in the South Pacific Ocean. The new species was formerly identified as Pomacentrus imitator (Whitley, 1964), which now appears to be restricted to the Coral Sea. The new species clearly differs from P. imitator on the basis of several color-pattern features, including a bright yellow ring that encircles the pupil, a more uniform body color (vs. contrasting pale scale centers and dark scale margins), a yellowish caudal fin (vs. whitish), and a small orange marking immediately above the large black spot that covers the pectoral-fin base (absent in P. imitator). Although meristic and morphological features are broadly similar, P. flavioculus has a strong mode of 14 anal-fin rays vs. 15 in P. imitator. Additionally, P. flavioculus usually has a greater preanal distance and almost always has a longer pelvic-fin spine. A phylogenetic analysis of concatenated mtDNA sequences shows the new species is 8.4% divergent (average pairwise distance) from its nearest relatives and is part of the broad Pomacentrus philippinus species complex.