Laboratory experiments were conducted under controlled conditions to test the toxic activity of two biopesticides, the formulated plant oil, natrilo and Bacillus thuringiensis (Berliner) as well as one chemical insecticide, pirimiphos-methyl against adults and larvae of the acarid mite,Tyrophagus putrescentiae (Schrank). Furthermore, the joint action of the three mentioned agents was investigated against adults of T. putrescentiae to determine the contact toxicity and some other parameters of biology alongside the effect on mite sterility. The results showed that pirimiphos-methyl was the premier for contact toxicity 24 and 48 h after treatment against adults and larvae of mite species. The plant oil natrilo placed the second order, while the effect of bacteria did not appear until the second day after treatment.  Concerning the effect of the tested materials on mite progeny parameters, the three materials demonstrated significant effects compared to untreated mite individuals. In addition, the tested materials had a positive effect on   sterility percentage.  The joint action of the tested compounds, the present results showed an additive and synergistic effect resulting in reaction of pirimiphos-methyl with natrilo and B. thuringiensis, respectively, while the combined effect of natrilo and B. thuringiensis gave antagonistic effect against the tested mite pest.