It is endemic to Ilha dos Alcatrazes, a small island about 35 km off the coast of São Paulo state, Brazil.

[2] Cycloramphus faustoi are known from a small valley in a dry stream bed at elevations of 20–100 m (66–328 ft) above sea level.

[1][2] Both males and females were spotted in rock crevices; they were wary and went into hiding when disturbed.

[2] Reproduction seems to occur in August when, following a rainy afternoon, males were heard calling at night and a females found guarding an egg clutch consisting of 31 eggs; the female did not leave even when disturbed.

[1] In the past, its habitat was threatened by fires caused by artillery training activities.