A cardiopulmonary resuscitation device configured to use a brain activation index as a CPR signal indicating a degree of cardiopulmonary resuscitation, comprising: an electroencephalogram detection unit configured to detect an electroencephalogram signal in the frontal lobe; a calculation processing unit configured to detect a brain activation index from the electroencephalogram signal received from the electroencephalogram detection unit, wherein the calculation processing unit is configured to calculate one or more of a burst suppression ratio, a beta ratio, and a relative synchrony of fast and slow wave (SynchFastSlow, SFS) as the brain activation index; a main body portion equipped with a chest compression unit configured to pressure a chest of a patient; and a holder configured to support the main body portion and be able to attach or detach the main body portion, wherein the holder further comprises: a main body holding unit which is U-shaped and bound to an edge of the main body portion; a holder leg portion which is connected to the main body holding unit to support the main body portion; and a back support portion, wherein one end thereof is connected to the holder leg portion as a means of supporting a back of a patient, wherein the back support portion is composed of two separate boards, and wherein a distance between the two boards can be adjusted to correspond to the width of the body of a patient. an electroencephalogram detection unit configured to detect an electroencephalogram signal in the frontal lobe; a calculation processing unit configured to detect a brain activation index from the electroencephalogram signal received from the electroencephalogram detection unit, wherein the calculation processing unit is configured to calculate one or more of a burst suppression ratio, a beta ratio, and a relative synchrony of fast and slow wave (SynchFastSlow, SFS) as the brain activation index; a main body portion equipped with a chest compression unit configured to pressure a chest of a patient; and a holder configured to support the main body portion and be able to attach or detach the main body portion, wherein the holder further comprises: a main body holding unit which is U-shaped and bound to an edge of the main body portion; a holder leg portion which is connected to the main body holding unit to support the main body portion; and a back support portion, wherein one end thereof is connected to the holder leg portion as a means of supporting a back of a patient, wherein the back support portion is composed of two separate boards, and wherein a distance between the two boards can be adjusted to correspond to the width of the body of a patient. a main body holding unit which is U-shaped and bound to an edge of the main body portion; a holder leg portion which is connected to the main body holding unit to support the main body portion; and a back support portion, wherein one end thereof is connected to the holder leg portion as a means of supporting a back of a patient, wherein the back support portion is composed of two separate boards, and wherein a distance between the two boards can be adjusted to correspond to the width of the body of a patient.