Abstract: Six hundred and two patients with urticaria (male 211, female 391) were studied. The patients with an age of onset from 10 to 30 years accounted for 57.6%. The percentage of patients with family allergy history was 37.9%. 48.2% of patients were believed to have definite precipitating factors, of which 31% referred to food allergy, mainly to shrimp and crab. 19.3% referred to physical factor such as cold, wind etc. 14.8% referred to,drug allergy, such as A.P.C. etc. 14.6% patients with urticaria complicated with allergic rhinitis and/or asthma. Among the inhaled antigens used for skin test, Dermatophagoides farinae (a house dust mite) was positive in 76%;house dust 71.4%;cockroach 52.9%. Among the food antigens shrimp and crab also had a higher positive rate (70.9% and 60.9%). Immunotherapy consisted of inhaled antigen extract plus histamine phosphate were used. Significant improvement was found in 20.8% of patients treated, and the total rate of effectiveness was 86.7%.