The design, fabrication, and characterization of a highly transparent and flexible monopole antenna optimized for the 3–6 GHz frequency band is presented in this paper. In traditional Transparent Conductive Oxide (TCO) designs, there is always a trade-off between the RF efficiency and transparency. Therefore, an Aerosol Jet® 5X system was used to directly print a silver nanoparticle mesh over a 50-µm polyimide (PI) substrate. With this fabrication method, a durable structure was yield which works well both electrically and mechanically with 85% transparency and a gain of −2.5 dBi. In order to demonstrate how the antenna is flexible and compatible with other devices, it was bent over a cylindrical body and was integrated with a commercial solar panel. The results show that impedance matching and radiation characteristics of the antenna remain stable under bending conditions, and no critical decrease was observed in solar energy harvesting. Consequently, this design presents a suitable solution for energy-autonomous IoT systems, smart windows, and CubeSat applications.