The Venezuelan Sylph (Aglaiocercus berlepschi) is a small bird in the hummingbird family, Trochilidae. It is restricted to a small area of north-eastern Venezuela and is classed as an endangered species by BirdLife International. It is sometimes considered to be a subspecies of the Long-tailed Sylph (A. kingi).

The male is 22 centimetres in length with the elongated outer tail-feathers accounting for 14-15 centimetres. Its plumage is mostly irridescent green. The throat is blue and the outer tail-feathers are violet, becoming blue towards the tips. The female is 9.5-11 centimetres long. The tail is shorter than that of the male but still fairly long and slightly forked. Females have a blue crown and white throat, breast and belly.

The Long-tailed Sylph is similar in appearance but does not overlap in range. Males of the subspecies caudatus have a mostly blue tail and no blue throat patch while males of the subspecies margarethae have green tips to the tail-feathers. Females have a rufous breast and belly.

The Venezuelan Sylph occurs in Sucre, Monagas and Anzoátegui states. It is found in the Cordillera de Caripe and Cerro Negro and there are unconfirmed reports from the Paria Peninsula. It inhabits forest and scrubland on coastal mountain slopes from 1,450 to 1,800 metres above sea-level. It is threatened by the loss and degradation of its habitat.