Allergic reaction to Cupressaceae and Taxodiaceae pollens appears to be on the increase in the last years in Italy. An epidemiological survey on this pollenosis was conducted in 12 Italian centers. The diagnostic panel consisted of seven Cupressaceae and Taxodiaceae genus (Cupressus sempervirens, Cupressus arizonica, Cryptomeria japonica, Chamaecyparis obtusa, Thuja orientalis, Taxus baccata, and Juniperus oxycedrus). A total of 3057 pollen-sensitized outpatients were examined. The study took place from November 1999 to March 2000. At the same time pollen counts were carried out. The prevalence of positive skin tests to the diagnostic panel is different in northern (9.2%), central (28.2%), and southern (20.1%) Italy, the general average being 18.4%. The average age of sensitized patients was 36.99. Monosensitized patients represent only 14.7% of total Cupressaceae-sensitized patients, their average age being higher than the polysensitized ones (43.3 versus 35.86). Distribution of symptoms is as follows: rhinitis (49%), conjunctivitis (32%), asthma (16%), and dermatitis (3%). Months with the highest levels of symptoms are February and March. The more frequent allergens at prick tests are Cupressus sempervirens (90%) and Cupressus arizonica (88.9%). The more reactive allergens are the Cupressus arizonica and Juniperus oxycedrus. The clinical data suggest that, in Italy at least, this pollenosis is on the increase. The use of more than one extract of Cupressaceae and Taxodiaceae genus increases the diagnostic sensitivity of the disease.