Abstract: Let p≥5 be a prime. For any integer h, the Hardy sum is defined by H（h,p）=sum(（-1）^{j+1+[（hj）/p]})from （p-1） to （j=1） which is related to the classical Dedekind sum. The mean values of the Hardy sum in short intervals are studied by using the mean value theorems of Dirichlet L-functions. 

Key words: Dedekind sum, Hardy sum, mean value, Dirichlet L-function