According to the resistance of bacteria to antibiotics, researchers have been trying to discover new antibiotics, among medical plants have played an important role. Stachys lavandifolia is one of these plants which has been used for treatment of pneumonia by the people of Boyerahmad in old traditional medicine. First, we provide hydroalcoholic extract of Stachys lavandifolia and then during several different experiments and by a plate method minimum inhibitory concentration (MIC) and Pseudomonas Aeruginosa growth obtained, and then diameter of this extract were compared with the diameter of the standard antibiotics. Stachys lavandifolia extract had a good effect on pneumococcal that concentrations mg / ml1000 formed a diameter equal to 3.5. At concentrations mg / ml 750 and mg / ml500 diameter of the respectively is mm33 and mm27 at MIC and MLC equal to mg / ml 25/31.Stachys lavandifolia extract had a modest effect on Pseudomonas concentration mg / ml1000 and mg / ml500 and mg / ml750 each zone that formed the MIC and MLC equivalent mm 15 mg / ml 500 registered. In concentrations 750mg/ml and 500mg/ml their diameters are respectively 33 mm and 27 mm that its MIC is equivalent to 31/25 mg/ml. Stachys lavandifolia extract had a modest effect on Pseuodomonas which in concentration of 1000mg/ml and 500mg/ml 750mg/ml each three have conformed 15mm halo that its MIC and MLC is equivalent to 500mg/ml. The result of this research showed that hydroalcholic extract of stachy Salavan-difolia in comparison with standard anti biotic has shown a positive antimicrobial effect, however, we hope with more efforts done on this plant , we can use the plant as an alternative to antibiotics, synthetic and semi-fabricated. So that, concentration of 750mg/ml its effect on streptococc pneumonia is better than all compared antibiotics, but about psedomonas aenginosa aerations in concentration of 1000 mg/ ml which was the highest concentration of our experiment from the most compared antibiotics, had a weaker effect.