An apparatus and a method of measuring a blood pressure of an examinee while detecting the body activity of the examinee uses a pressurizing unit of a blood pressure gauge having first and second driving modes for pressurizing a cuff. A central processing unit classifies signals, which represent the movement, the position, or the direction of the blood pressure gauge detected by a sensor installed in a body of the blood pressure gauge, into a plurality of groups, and selectively performs the first driving mode or the second driving mode according to signal bands classified into the groups. The central processing unit is configured to generate blood pressure data so that the variation in the blood pressure of the examine is exactly determined according to the activity degree and the posture of the examinee.
