Over the past decade, radio-frequency identification (RFID) technology has attracted significant attention and become very popular in different applications, such as identification, management, and monitoring. In this study, a dual-band microstrip-fed monopole antenna has been introduced for RFID applications. The antenna is designed to work at the frequency ranges of 2.2–2.6 GHz and 5.3–6.8 GHz, covering 2.4/5.8 GHz RFID operation bands. The antenna structure is like a modified F-shaped radiator. It is printed on an FR-4 dielectric with an overall size of 38 × 45 × 1.6 mm3. Fundamental characteristics of the antenna in terms of return loss, Smith Chart, phase, radiation pattern, and antenna gain are investigated and good results are obtained. Simulations have been carried out using computer simulation technology (CST) software. A prototype of the antenna was fabricated and its characteristics were measured. The measured results show good agreement with simulations. The structure of the antenna is planar, simple to design and fabricate, easy to integrate with RF circuit, and suitable for use in RFID systems.