An apparatus for estimating blood pressure is provided. The apparatus for estimating blood pressure according to an example embodiment includes: a sensor configured to measure a photoplethysmogram (PPG) signal from an object; and a processor configured to detect a position of a dicrotic notch based on a local maximum point and a local minimum point of a second-order derivative signal of the PPG signal, to obtain a first value and a second value from a first section and a second section of the PPG signal divided based on the dicrotic notch of the PPG signal, to obtain a pulse pressure feature value based on the first value and the second value, and to estimate blood pressure based on a variation in the obtained pulse pressure feature value compared to a reference pulse pressure feature value.