A non-burning type flavor inhaler, comprises: a housing having an airflow path that continues from an inlet to an outlet; an atomizer configured to atomize an aerosol source without burning; a sensor including a capacitor, the sensor outputting a value indicating electric capacitance of the capacitor, the electric capacitance changed depending on a puff action of a user; and a controller configured to detect a start or an end of a puff duration on the basis of an output value that is output from the sensor. The controller detects the start or the end of the puff duration when an inclination formed by two or more of the output values has a predetermined sign and when an absolute value of the inclination having the predetermined sign is larger than a predetermined value.