This paper presents a data acquisition and monitoring system for a gas turbine. The proposed system entitled C-Tune DAS plays an important role to make an analysis of the real-time operation of the gas turbine under maintenance. The designed LabVIEW based software is divided into three parts according to their original functions, i.e., data acquisition, data analysis with display, and data storage. The data acquisition part receives data from a PMS (Plant Management System) server and two cFPs (Compact-Field Point). To verify the validity of the developed system, it is applied to gas turbines in the combined cycle power plant in Korea.