The method for determining a depression state of the present invention comprises the steps of: measuring a pulsation interval of a subject, and an acceleration or an angular velocity associated with a movement of the subject (that is hereinafter referred to as an “activity”)； and determining the subject to be a depression state when at least one of the following conditions [A] and [B] is satisfied: [A] In an awaking time zone of the subject, at least one of the following formulas is calculated and satisfied； the pulsation interval×the activity<；C1, HF×the activity<；C2, (LF/HF)/the activity>；C3； [B] In a sleeping time zone of the subject, at least one of the following formulas is calculated and satisfied: the pulsation interval/the activity<；C4, HF/the activity<；C5, (LF/HF)×the activity>；C6.
