The coccinellid beetle(Chilocorus nigritus[Fabricius], Coccinellidae: Coleoptera) was successfully introduced from India during 1985, as a biocontrol agent against the coconut scale insect(Aspidiotus destructorSign, Diaspididae: Homoptera) which infests coconut palms in south Oman. A total of 683 adults ofC. nigrituswere released during January to April 1985. The data obtained show the rapid build‐up of the predators and the subsequent decline in the host population. After 24 months from the last release (April 1985) the median number of coconut scale insects per leaf area decreased to the minimum number, since it ranged between zero and 49.7 scales, while it ranged between 174.8 and 285.0 scales before release of the predator. The coccinellid predator(C. nigritus)rapidly built up in the release site and up to 12 km distant after 6 months from the last release, since it ranged between 38.2 and 144.5 predators (adults and larvae combined) per palm. In Taqa locality, which is about 16 km from the release site, the predator appeared and was recovered after 18 months from the last release. Thus, the use of pesticides against this pest is no longer needed in the southern region of Oman. The potential danger of the studied pest, coconut scale insect(A. destructor)was greatly reduced in the release site, and in all locations under investigation all over Dhofar plain after 24 months from the last release as a result of predation of the newly established coccinellid beetle(C. nigritus)which was an efficient predator against this pest.