A cardiac function measurement and evaluation device is provided to measure and evaluate cardiac function in patients with atrial fibrillation, sinus arrhythmia, and the like, using thoracic impedance data and electrocardiogram data. By creating a two-dimensional scatter plot in which (dZ/dt)min values and preceding RR intervals (RR1) corresponding thereto, and the like obtained by thoracic impedance measurement, are plotted, it is possible to visually and easily evaluate the state of cardiac function in patients with atrial fibrillation and sinus arrhythmia. Using the measurement and evaluation device of the present invention makes it possible to perform examinations easily and repeatedly with less burden on patients. Therefore, it is possible to provide very useful information for diagnosing heart disease, selecting drugs, and the like.