Thermal printers are widely utilized for medical reference hard copy systems because of their advantages, which include compactness, high-quality printing, high speed, high reliability, and low noise. Especially for diagnostic ultrasound systems and electronic endoscopes, monochrome direct thermal printers and dye sublimation thermal printers are the standard. The use of hard copies, which is mainly used for printer output, is expected to be lost due to recent digitalization. However, in actuality, the laws and regulations of each country and the print output application rooted in the medical workflow still prevail. This paper discusses the features of the thermal printer products and reports their usage status in the medical field.