Pityogenes bidentatus (H rb st.) is an im p o r ta n t p est esp ecia lly on sp r u c e a n d o th e r c o n ifer fo rests in E a ste rn B la ck S ea R eg io n . I f n o p reca u - tio n s are ta k en a g a in st tlıis p est, it m a y b eco m e a p rim a ry p est o n y o u n g c o n ifer trees a n d m a y İdil th em . In tlıis stu d y , th e b io lo g y o f P. bidentatus vvas stu d ied an d its six teen p red a to ry in sects w e r e d eterm in ed . E ffe c tiv e n e ss o f th e p red a to rs in th e b io - lo g ic a l co n tro l vvere also d eterm in ed b y th e ca lcu la tio n o f p o p n la tio n d en sity o f each p red a tö r. Tlıanasimus formicarius (L .) an d Rhizophagus dispar (P a y k .) w ere fo u n d to b e rela tiv ely m o re e ffe c tiv e in tlıe co n tro l o f P. bidentatus th a n o th e rs. In a d d itio n to th e se, tw o o th e r p red a tö r in sec ts, Nemosoma elongatum (L .) an d Paraphloeus linearis F ., vvere a lso fo u n d that th e y p referred to feed o n P. bidentatus.