Abstract: Hexane, chloroform, methanol and water extracts of aerial part of a high altitude Himalayan medicinal plant Valeriana wallichii DC. (Valerianaceae) were tested for their in vitro antimicrobial properties against animal and plant pathogenic bacteria using disc diffusion method. Aqueous extract showed the highest activity against Staphylococcus aureus (23±1.0 mm zone of inhibition, MIC 250 and MBC 500 μg mL-1) followed by methanol extract against Bacillus subtilis (20±1.0 mm ZOI, MIC 31.25 μg mL-1 and MBC 500 μg mL-1), Staphyloccocus aureus (19±0.8 mm ZOI, MIC and MBC 125 μg mL-1) and hexane extract against Bacillus subtilis (18±1.2 mm ZOI, MIC and MBC 125 μg mL-1). Chloroform extract showed the least activity against the test bacteria. The inhibitory potential of V. wallichii extracts was found very notable as compared to Ampicillin (10 mcg) and Erythromycin (15 mcg) which were used as positive control against these tested microorganisms and therefore this plant can be used as a good source of antibiotic substances for possible treatment of bacterial infections of both plants and animals.