Abstract: Schottky diagnostics are often used in circular accelerators and in storage rings. A brief introduction on the longitudinal Schottky signal basics and a report on the elements of Schottky diagnostic system at CSRe are presented. The system consists of a pair of Schottky electrodes, λ/4 helical resonator, low noise amplifier and data acquisition device. Test measurement results of the frequency measurement and sensitivity measurement with 78Kr36+ beam of 481.88 MeV/u circulating in the storage ring CSRe are obtained. The results show that the system is sensitive to the beam current larger than 82 nA.