Glucose-aspirin (GA) was synthesized by conjugating aspirin (ASA) to glucose. The water solubility and biological activity of GA was studied in comparison to aspirin. The human serum protease activity on the ester showed a slower hydrolysis rate, compared to ASA. Glucose-aspirin was sevenfold more water soluble than aspirin and it was about 8- to 9-fold more active in inhibiting cell growth than aspirin in their anti-cancer cell culture activity on breast (SKBR3), pancreatic (PANC-1), and prostate (PC3) cell lines, whereas the activity was similar on a benign non-cancerous cell line (WI 38). In conclusion, GA is a highly water soluble derivative of aspirin. Although the serum hydrolysis for GA was slower, there was significant anti-cancer activity at the doses studied under the experimental conditions.