In order to warn the health authorities in our region about the economic damages that a hemorrhagic dengue epidemic may cause, it was decided to study and publish the estimated cost of the Cuban epidemic in 1981, during which 344,203 diseased were reported, 10312 severe cases and 158 deceased. Economic costs include hospitalization expenses, assistance in emergency units, social security, expenses in out-patient treatment, goods not produced and expenses in the anti-vector campaign. Probably, this epidemic which could be controlled in about 4 months, has been the one causing most economic damages to date.