Mosquito bites should be avoided because of the risk of contracting parasitic and viral diseases such as malaria, dengue fever, and several encephalitides. Although humans have been said to suffer more mosquito bites after ingesting liquor, little is known about whether that is true. Thirteen volunteers (12 men from 20 to 58 years old and a 24-year-old woman) were chosen as test hosts and a 30-year-old man was established as a control. We measured ethanol content in sweat, sweat production, and skin temperature before and after ingestion of 350 ml of beer (ethanol concentration 5.5%) by volunteers and compared them with a control subject. Our study demonstrated that percent mosquito landing on volunteers significantly increased after beer ingestion compared with before ingestion, showing clearly that drinking alcohol stimulates mosquito attraction. However, ethanol content in sweat and skin temperature did not show any correlation between alcohol ingestion and mosquito landings. This study shows that persons drinking alcohol should be careful about their increased risk to mosquito bites and therefore exposure to mosquito-borne diseases.