A Modified NaY/ZSM-5/IDC zeolite composite with Cu2+ has been succsessfully prepared on the surface of quartz based Interdigitated Capacitor (IDC). The ZSM-5 was synthesized with double template using hydrothermal method and NaY zeolite was synthesized using sol-gel method. Powder XRD patterns confirmed that structures were ZSM-5 and NaY zeolites. Surface area analysis using BET method are 472,27 m2/g with pore size 2,32 nm for mesoporous ZSM-5 and 392,81 m2/g with pore size 1,6 nm for microporous NaY zeolite. NaY/ZSM-5/IDC and Cu/NaY/ZSM-5/IDC prior ammonia gas sensor testing using Electrochemical Impedance Spectroscopy (EIS) method. The composite has different sensitivity in range concentration of ammonia 0-300 ppm. The Cu/NaY/ZSM5/IDC has higher sensitivity compared to NaY/ZSM5/IDC.