The demand for wireless power transmission is increasing day-by-day to power up smart sensing and low energy devices. The most emerging field in the environment of wireless power transmission is a health monitoring system, which is power-driven by RF energy harvesting. RF energy harvesting is accomplished by using a device called “rectenna.” The rectenna consists of a sensing antenna that receives ambient signals available freely in the environment and sends them to the rectifier, which converts the received AC signal into the DC waveform. Further, the converted DC voltage can be used in biomedical devices for health monitoring. This device may be implanted or wearable depending upon the requirements and it ensures monitoring of different organs of the body remotely. Due to the use of RF energy harvesting, the often replacement of device battery is not required and a device can monitor health for the long term or sometimes everlasting. The design and analysis of different antenna types used for RF energy harvesting and different techniques involved in the smart health monitoring system are reviewed and presented in this chapter. The chapter also investigates the advantages of 106printed rectenna such as light-weight, compact size, and their compatibility with the body organs.