This paper proposes an efficient triband rectifying circuit based on the Schottky diode for energy harvesting applications. Using a new compact impedance matching network, the rectifying circuit is matched at the GSM 1800, UMTS 2100, and WiFi 2450 bands. The design uses a substrate of Rogers Duroid 5880 with a thickness of 1.575 mm and εr=2.2. High Power Conversion Efficiency (PCE) is achieved in the rectifying circuit by using a microstrip DC pass filter for fundamental and second harmonic rejection. With a 2.8 KΩ circuit load and an input power of 0 dBm, the simulated efficiencies obtained at the GSM 1800, UMTS 2100, and WiFi 2450 bands are 45%, 19%, and 58.5%, respectively. For an input Radio Frequency (RF) power of -5 dBm, the efficiencies obtained are 49%, 38%, and 50 %, respectively, at a load resistance of 2.8 KΩ using an ADS simulator. There are numerous applications for the proposed triband rectifying circuits, which can power low-power sensors and electronic devices.