10.22376/ijpbs.2019.10.1.p1-12 Volume 7 Issue 1 2016 (January - March) lessThan i greaterThan Thuja orientalis lessThan /i greaterThan is a well known red cedar commonly used as an externally applied tincture or ointment for the treatment of ringworm, warts and thrush. Antibacterial potentiality of the crude extract and different solvent extracts of the strobilus of lessThan i greaterThan Thuja orientalis lessThan /i greaterThan was evaluated on microbial strains like gram negative lessThan i greaterThan Pseudomonas fluorescens lessThan /i greaterThan , lessThan i greaterThan Pseudomonas putida lessThan /i greaterThan and gram positive lessThan i greaterThan Bacillus mycoides lessThan /i greaterThan , lessThan i greaterThan Bacillus licheniformis lessThan /i greaterThan using agar well diffusion method during the present study. Chloroform: methanol (1:1 v/v) extracts showed the best result against the test bacteria. M.I.C. values of the aforesaid extract were found to be 0.36 mg/ml and 0.96 mg/ml against lessThan i greaterThan Pseudomonas fluorescens lessThan /i greaterThan and lessThan i greaterThan Pseudomonas putida lessThan /i greaterThan respectively while 1.09 mg/ml and 1.12 mg/ml for lessThan i greaterThan Bacillus mycoides lessThan /i greaterThan and lessThan i greaterThan Bacillus licheniformis lessThan /i greaterThan respectively. The chloroform: methanol (1:1 v/v) extract of strobilus of lessThan i greaterThan Thuja orientalis lessThan /i greaterThan may act as a novel source to obtain an effective antibacterial agent. DEVALEENA MUKHERJEE , ANUSHREE SINGHA RAY, KUNTAL BHATTACHARYA, AND GOUTAM CHANDRA : Thuja orientalis, Strobilus, Solvent Extracts, Antibacterial activity, Minimum inhibitory concentration. 156-160