The study of the effect of Giardia lamblia and Helicobacter pylori organisms coexistence on the activities of urease and lipase enzymes was the aim of this work which was done through choosing 50 cases of giardiasis in addition to 10 normal individuals chosen as a control group (free from giardiasis). It is well known that H. pylori is considered one of the most important causes of gastric and duodenal inflammations which could predispose to ulcers and hypochlorhydria leading to increased susceptibility to giardiasis as it is known that HCl acts as a chemical barrier to microbes. The biochemical tests were done to investigate the activity of both urease and lipase enzymes extracted from the gastric juice of patients and controls. A significant increase in urease activity in the group having combined infection (giardiasis and H.pylori) than the group infected with G.lamblia alone and the control group was found. The same findings were obtained regarding the lipase activity. In the present work, both infections H. pylori and G. lamblia coexisted in 75% of epigastric pain cases which could be explained on the basis that both organisms predispose to each other.