The microstrip antennas are currently evolving towards smaller size and higher integration, which makes the electromagnetic-thermal effects of the antennas significant. Tapered Slot Antennas, characterized by their simple structure, low profile, high radiation efficiency, and wide operating bandwidth, have been widely used in the field of wireless communication. In this paper, starting from the steady-state conduction equation and introducing appropriate thermal boundary conditions, an analysis of the electromagnetic-thermal effects of Tapered Slot Antennas is conducted.