Frankliniella occidentalis is the prevalent pest causing serious damage in protected pepper cultivation. Synthetic insecticides have been and are still used to control this insect. However, these chemical applications create enormous problems such as environmental pollution, resistance to insecticides, ineffectiveness, residue, etc. This study was conducted in order to assess the biological control possibilities for F. occidentalis. Orius niger and Orius laevigatus were tested to determine their optimum dose and selecting of convenient predators considering their comparable performance after releasing by 1, 2, 4 and 6 adult m(-2) doses against this pest. These trials were carried out in the 2003-2004 and 2004-2005 sweet pepper growing period in Antalya. In first year trial, predators were only released one time at the beginning of the growing season. However, single autumn release did not lead to sufficient control of the pest at the beginning of spring term. Therefore, a second release was done, which was required in the spring period in the second year. O. laevigatus showed a more rapid colonization of plants than O. niger and led to efficient control of F. occidentalis on sweet pepper with two releases of 4 adult m(-2) in October and March.