The aim of this research was to investigate the effectiveness of fluvalinate (on wooden bars), amitraz (on paper strips) and coumaphos (liquid) against Varroa jacobsoni in honeybee (Apis mellifera L.) colonies. This research was carried out on 24 A. mellifera colonies in the Çukurova region in spring 1998. The colony strength, the area of sealed brood and the rate of infections were evaluated before and after the chemical applications. The level of varroa contamination for each colony was determined on 200 brood bees at the pupa stage and on 150-200 adult bees. After the application, dead fallen and alive drugged mites and dead bees on the modified bottom board were counted every day for sixteen days. Then the effectiveness of the three chemical applications was determined and the results statistically evaluated with the Henderson-Tilton method. The data obtained were evaluated statistically. Fluvalinate, Amitraz and Coumaphos were 97.3%, 91.1% and 83.4% effective on V. jacobsoni respectively. Colonies in the control group without treatment were strongly affected by varroa, resulting in very low honey yield. Conclusions from this research are that varroa is a very serious problem for Turkey, with migratory type management spreading this infection. If no precautions are taken, honey gathering will be impossible economically, and colony loss probability will be very high at the end of the season.