In the framework of the semiclassical theory, the authors develop an analytical approach on electromagnetically induced transparency (EIT) in the medium that consists of the five-level cascade scheme of cold 85Rb atoms. In the weak field limit of the probe light, an analytical representation of EIT spectra has been derived for the first time. Signatures of EIT spectra, including transparency efficiency, have been investigakd. the theoretical results agree well with experimental observations.