The concentration of airborne pollen from Cupressaceae was regularly monitored++ in Lisbon during 1997 and 1999, and the phenology of flowering cypress was studied in several species of the genus from 1992 to February 2000. Both methods showed a peak of pollen abundance during the month of February, with the airborne pollen concentration decreasing strongly to March and April. The results obtained are in accordance with the literature for the Mediterranean area, but in Lisbon the peak started and finished earlier than in other Mediterranean towns already studied.