Hallux valgus interphalangeus is a deformity occurring between the proksimal and distalphalanges of the great toe. This relatively uncommon form of hallux valgus is frequently congenital in origin. Acquired hallux valgus interphalangeus can be caused by traumatic arrest of growth of one of the phalangeal epiphyses, malunited fracture of phalanges, rheumatoid arthritis and arthrogryposis multiplex congenita. In this paper, 2 cases with hallux valgus interphalangeus who had surgery were discussed. One of them was congenital in origin and bilateral. The other one had a complex syndactyly of the first and second rays of her left foot. It is our belief that the deformity developed secondary to this complex syndactyly.