Turkey is first among all hazelnut producing countries. However, it lags far behind them in terms of amount harvested per unit area. A main reason for this is that hazelnut has many agricultural pests that can not be effectively controlled. Chemical pesticides utilized to control these pests have hazardous effects on the environment. Increasing problems with resistance of these pests to most commonly used synthetic insecticides have spurred the search for alternative pest management strategies that would reduce reliance on synthetic insecticides. Biological control of hazelnut pests is an alternative control method to chemical pesticides. It is very important ecologically because of production of honey, milk and fish in the surrounding areas of hazelnut fields in Turkey. Several promising bacteriological studies have been made to find some biological control agents against these pests in Turkey. This paper presents a review of the current status of bacteriological studies on biological control of hazelnut pests in Turkey.