<正> This paper reports the stroke incidence rates in the People’s Republic of China（PRC）in 1986.A total of 5790864 people from 199 locations sampled from all parts of the PRC（Taiwanprovince excluded）were investigated and among them 6367 complete stroke cases were found.Theincidence rate was 109.95 per 100000 people and its 95% CI was 107.25～112.65/100000.The inci-dence rate adjusted using the population composition of the urban and rural areas of the PRCin 1986 was 110.58/100000.The incidence rate standardized by the direct method using thePRC population in 1982 was 84.07/100000

and the incidence rate standardized using theworld standard population was 115.87/100000.The incidence rates of the various provinces werecounted respectively

and the relationship between the incidence rates and the geographical locationswas analysed correlatively and regressively.Positive correlation and linear regression were found be-tween the incidence rotes and the latitudes and the longitudes

that is to say

the incidence rates in-creased gradually from the south to the north and decreased progressively from the east to the westin the PRC.The stroke incidence rates were higher in urban districts than in outskirts inbig cities.When the distribution of case number in months was analysed using the methods of thetest for trend and circular distribution

a peak significant in statistics was found in January althoughit was not very high.The stroke incidence rates rose gradualy with age

and the relationship be-tween the incidence rates and age could he fitted with the Logistic curve.