Abstract A 10 day survey was carried out off Western Sardinia during summer 1997. Conventional observation methods were used onboard a 12 meter motorsailer. A zig-zag sampling of 584 kilometers and 65 hours of observation were done, during which 21 groups of cetaceans were sighted. Five species were observed: the fin whale (3 sightings), the striped dolphin (10 sightings), the common dolphin (6 sightings), the bottlenose dolphin and the sperm whale (1 sighting each). High sighting frequencies were obtained for the striped dolphin in the pelagic area and for the common dolphin in the slope area, suggesting that each species favours a distinct habitat. This study is in reasonable concordance with the few results already published on the subject. However more research must be done in this area.