The study investigated the phytochemical activities of crude extracts of some beneficial plants, Uziza leaf (Piper guineense), Scent leaf (Ocimum gratissimum) and Bitter leaf (Vernonia amygdalina) against some clinical isolates. Ethanol, methanol and aqueous solution were used in the extraction process. The antimicrobial activity of the extracts were screened using the disc diffusion method. The phytochmical screening of the plant crude extracts revealed the presence of alkaloids, glycosides, saponnins, tannins, fats and oil in varying proportions and the absence of flavonoids. The aqueous extract of the leaves have more potential as an antimicrobial agent than its ethanolic extracts. It was observed that the hot water extracts of Piper guineense and Ocimum gratissimum showed activity against all the test organisms except Proteus spp and Enterobacter spp. This may mean that heating of these spices during cooking would not inactivate the ingredients that are active against the susceptible bacteria strains. The cold water extract of Vernonia amygdalina exhibited activity at (400mg/ml) on Salmonella guineum, Proteus, Staphylococcus scuiri, Enterobacter spp, Escherichia coli and Staphylococcus aureus and inactivity on Bascillus spp. Also, the cold water extract of Ocimum gratissimum had activity only on E.coli at 400mg/ml while cold water Piper guineense was not active against the test organism, suggesting that cold water as a solvent could dissolve the active constituents of Vernonia amygdalina better compared to Ocimum gratissimum and P.guineense extract. It was observed that there were differences in susceptibility of test micro organisms used in the research to each extract. Escherichia coli was the most inhibited organism by P.guineense, Vernonia amygdalina and Ocimum gratissimum with a mean inhibition zone diameter (IZD) of 3.99mm while the least inhibition was an average IZD of 14.7±0.3mm. in all, this research shows that Uziza leaf (Piper guineense), Scent leaf (Ocimum gratissimum) and bitter leaf (Vernonia amygdalina) have a measure of antimicrobial activity and also potentials for use as herbal decoction. More studies need to be carried out to determine how these leaves can be used as preservatives in what form, what quantity and how long.