Abstract: Specific Absorption Rate (SAR) is a mandatory parameter for the personal safety of electromagnetic radiation involving wireless communication products. Due to the changing nature of the devices under test, the measurement system and methods need to be updated, which imposes new requirements for the validation of the measurement system. Based on an in-depth understanding of the validation methods in current standards, we analyze and measure the traditional validation methods for three steps: extrapolation routine verification, probe linearity verification, and modulation response verification. Using electromagnetic simulations and experimental measurements, we extended these validation methods to meet new testing requirements. The experimental results show that the extended validation methods are feasible and stable. As reference values were obtained through self-developed methods, the validation methods can be extended, allowing for customized validation configurations, such as validation points. This provides technical support for the research on validation methods for new and domestic SAR measurement systems.