Increase in use of antibiotics in recent days have resulted in development of drug-resistant bacteria, which ultimately can be life threatening. As an alternative solution to this problem, we have used homeopathic medicines for our study of antibacterial activity of E.coli, a gram negative bacteria. Activities of Silicea, Sulphur and Calcarea carb (Calc carb) at the potency 6 C, 30 C, and 200 C were observed using general spread plate techniques. For different potencies of each of these drugs, activities are different. Among these three drugs sulphur is found to be more active. At 200 C potency silicea and Calc carb had their minimum colonies, whereas for sulphur at 30 C potency growth is inhibited.