Abstract: Balanced filter can achieve good performance in match, filter characteristic, and insertion loss, but only in narrow band application. Surface mounted filter and balun used at the same time not only take up larger area, but also may reduce system performance because of interfere between them. The LC filter and broadband Marchand balun are realized in the same LTCC substrate by coupling capacitor. This way can not only reduce size of devices, the two components can also compensate each other. Balun improves the attenuation characteristics of the filter; filter improves the matching characteristics of the Balun for broadband applications. The proposed balun-filter has center frequency of 7.65GHz, bandwidth of 1GHz, amplitude mismatch less than 0.2dB, phase mismatch less than 4.5°, attenuation more than 60dB at 5GHz, and attenuation more than 40dB at 9GHz. The size of this proposed balun-filter is 7mm*3mm*0.6mm.