In this paper, a novel Integrated Filter-Antenna (IFA) is proposed. The filtering element is based on the simple quasi-elliptic bandpass filter with capacitive loading, in which the fundamental resonance is significantly attenuated and thus the intrinsic harmonic resonance associated with two zeros is deliberately utilized in order to realize a quasi-elliptic bandpass response with simultaneous control of zeros and bandwidth. The slot antenna is developed by a symmetrical C-shaped slot and a microstrip fed line which fed at the center. The simulations and measurements of a 2.4 GHz prototype bandpass filter and a 2 GHz slot antenna are presented in this work. The isolations between the filter and the antenna are all more than 20 dB.