In this letter, a miniaturized broadband power divider with novel configuration is proposed. Coplanar transmission lines of CPW and cascaded two sections of coupled ACPSs are utilized to achieve broadband performance. MIM capacitors are loaded at each ends of the ACPSs to realize size‐reduction along with ground equalization. Design equations are given in detail. The occupied area is about 3.5 × 0.6 mm2 and a significant size reduction of 61% is achieved. The fabrication process of this power divider with coplanar transmission lines is compatible with GaAs MMIC process. Broadband performance and perfect impedance matching are revealed by the measured results that the return loss S11 and S22 are both lower than −15 dB across the entire X‐band, 8–12 GHz. Good isolation and dividing properties are obtained with S23 better than −10 dB and S21 around −3.5 dB. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:1427–1431, 2017