The use of B ultrasound machine includes the following aspects: First, the use of B ultrasound machine to choose a stable power supply, to have a ground wire, equipped with a voltage regulator, the power cord of the B ultrasound machine plugged into the voltage regulator. Second, skilled mastery of the function of each indicator key on the ultrasound instrument panel, when examining patients, the switching steps of the function keys should be very skilled, if the image display is not good to adjust. For example, when examining superficial organs, such as the thyroid gland and breast gland, choose a high frequency probe with a frequency of 10-12 Hz. For example, when examining superficial organs, such as the thyroid and breast, choose a low frequency probe with a frequency of 3.5-5 Hz. If examining the heart, choose a medium frequency probe with a frequency of 6-8 Hz. Fourth, after doing the patient every day, first gently wipe the probe clean with a soft cloth, then disinfect the probe and lightly place it on the probe holder. Regular cleaning and dusting of ultrasound instruments and regular infrared disinfection of the examination room should be carried out.