Recently, β-Ga2O3 FETs have been introduced [1]-[3] as potential devices for high power, switching, and RF applications with increased performance and more cost effective means of production when compared to GaN or SiC. Documented material properties leading to a Baliga [4] figure of merit nearly four times that of GaN [1], indicate potential for reduced specific on resistance at higher breakdown voltages if theoretical material characteristics can be exploited. To achieve projections, however, low thermal conductivity of ∼13 W/mK [5] [6], less than a tenth of GaN or SiC [7], must be managed. We present electrical characterization for ß-Ga2O3 MOSFETs using both static and pulsed measurement systems. Our results show the extent of thermal effects and provide a basis for developing test protocols to effectively characterize the devices without inducing thermal effects or degradation.