Abstract: A traditional decoction made from the leaves of Psidium guajava (guava) and rootstalk of Zingiber officinale (ginger) prepared in schnapps (42% v/v ethanol: water) that is widely used in Akoko North community in Ondo State, Nigeria to treat many diseases was evaluated for antibacterial activity on some common bacteria that cause diarrhea in south-west Nigeria. Its activity was compared with that of Psidium guajava leaf extract in schnapps without Zingiber officinale and Psidium guajava leaf extract in water with or without Zingiber officinale. The effect of storage temperature on the antibacterial activity of the extracts was also investigated. All the extracts inhibited the growth of all the test organisms which include Enterotoxigenic Escherichia coli (ETEC), Shigella dysenteriae, Staphylococcus aureus, Salmonella tyhpi but the leaf extract in schnapps without Zingiber officinale gave the highest inhibition on the growth of the test organisms with diameter ranging from 7.0-16.0 mm. These values were comparable with the inhibition mediated by most of the antibiotics used. The inhibitory effect reached climax by the third day and declined to zero level for most of the test organisms by the fifth day. The storage temperatures used (4, 20, 28±2°C) did not have significant effect (p≥0.05) on the potency of the prepared extracts on the growth of the test organisms. It is being suggested that in the absence of immediate medical attention when one is having running stomach, this decoction may be used as first aid in the treatment of bacterial diarrhea caused by these organisms.