An epidemiological analysis study of Dengue Haemorrhagic Fever (DHF) suspected cases has been done at two hospitals in Jakarta; namely Ciptomangunkusumo Hospital and Sumber Waras Hospital, from 1986 to 1987. From 3,164 suspected DHF cases there were 1,868 paired serum and all of them were tested with H.I. against D2 antigen from PN Biofarma based on microtechnique method by Qark & Cassals. Among them 1£10 were positive ( 70.1%) according to WHO Criteria. Analysis of DHF cases with positive H.I. test shows that the number of DHF cases started to increase continuously from February 1986, until June 1987 with a second and third peak on January and April 1987. The dominant age group were 5 - 7years old children (30.1%) and 15 - 20years old adults (15.8%). There were no significant difference between males and females, although the frequency among females was higher then males. Factors which influence those patterns : sex, age, seasonal variation were discussed in detail in this paper.