A battery-free electronic blood pressure measuring apparatus comprising a cuff (40), an airbag (22) to push air into the cuff (40), a power generation unit which has a generator (42) and an operating handle (28) coupled with the wall of the airbag (22) to generate electrical power, and a display device (44) to receive electrical power from the power generation unit, detect a blood pressure signal from the cuff (40), generate and display a blood pressure measurement. A method for electronically measuring blood pressure with a battery-free sphygmomanometer comprises pressing an airbag and a generator-driving structure attached to the airbag wall, which leads to electrical power generation and cuff inflation by the airbag at the same time, and measuring the blood pressure with the generated electrical power.