Ultrasonic diagnostic equipment is widely used in the medical field today. In particular, it is an established and indispensable diagnostic technology in obstetrics and gynecology. Recently, however, as high-frequency and high-intensity ultrasound is being increasingly used to expand diagnostic target regions and improve the diagnostic performance, it is necessary to validate the safety of ultrasonic diagnostic equipment. The effects of ultrasound radiation on the human body, including thermal effects, which generate heat, and non-thermal effects, which are mechanical oscillations, need to be investigated. Thermal effects occur as the ultrasound propagating in the body is attenuated and the energy is converted to heat. It is important to understand thermal effects when investigating the safety of ultrasonic diagnostic equipment. To predict thermal effects, it is critical to analyze the sound wave propagation inside the living body, obtain the calorific value of the ultrasound intensity, and analyze the heat conduction inside the living body. In this study, we used numerical simulations to analyze sound wave propagation and heat conduction for focused ultrasound irradiation. We also conducted an analysis of sound wave propagation and heat conduction in the presence of a thick blood vessel in the region of interest inside the living body and studied the effect of blood flow on heat diffusion.