[en] The dielectric function in a turbulent plasma is derived based on the linear response theory, in which a summation of the infinite series is made in order to get the pair-correlational effects exactly. This infinite sum can be performed with the aid of diagram techniques and reproduces the dielectric function obtained before by Kono and Yajima. The complex conductivity is also derived by using a similar diagram technique and rightly agrees with that obtained kinetic-theoretically by Nishikawa and Ichikawa. (auth.)