Ultra-wideband technology (UWB) is used for transmitting large amount of data over wide frequency range. There is always a trade-off between gain and bandwidth of micro-strip patch antenna for UWB. It is difficult to obtain wideband and high gain in an antenna simultaneously. In the proposed design, a compact, high-gain ultra-wideband tree-shaped radiating patch antenna with band notch characteristics is designed. The radiating patch is printed on FR4 substrate with permittivity 4.4. Tree-shaped radiating patch and defected ground structure (DGS) provides a wideband over 2.8–11.6 GHz frequency range. For providing stop-band notches in the existing wireless technologies, two complementary split-ring resonators (CSRRs) are used. By etching square complementary split-ring resonator (CSRR) in the feed, a stop-band notch at WLAN (5.1–5.9 GHz) frequency range is obtained, and a single CSRR in the patch provides a notch at WiMAX (3.3–3.6 GHz) frequency range. The antenna has varied positive gain over all the frequencies other than notched bands. Maximum gain of 5 dB at 9 GHz and minimum of 0.4 dB at 4 GHz is obtained. Antenna is simulated using high frequency structure simulator (HFSS) software. The designed antenna is validated by comparing simulated results with measured results. © 2018, Springer Nature Singapore Pte Ltd.