PROBLEM TO BE SOLVED: To provide an apnea condition detection system capable of grasping the presence or absence of an apnea condition by detecting the characteristics of CVHR from a beat interval by a simple calculation. SOLUTION: The beat interval measuring means for measuring the heart beat interval of the subject, the short-time average beat interval calculating means for calculating the short-time average beat interval, and the long-time average beat interval are calculated. Long-time average beat interval calculation means, beat interval valley calculation means for calculating the difference between short-time average beat interval and long-time average beat interval, short-time average beat interval and long-term average beat interval In the time series of the difference between and, a place where a value smaller than a predetermined valley depth threshold V exists is determined as one beat interval valley, and a beat interval valley determining means, and within a predetermined determination time. The number of valleys between pulsation intervals is compared with a predetermined number of valleys within a predetermined determination time, and the number of valleys between pulsation intervals is compared with a predetermined threshold value P of abnormal valleys. If it is above, it is provided with a valley number comparing means for determining that the state is an apnea. [Selection diagram] Figure 1【課題】CVHRの特徴を拍動間隔から簡単な演算で検出して無呼吸状態の有無を把握できる無呼吸状態検出システムの提供。【解決手段】対象者の心臓の拍動間隔を測定する拍動間隔測定手段と、短時間平均拍動間隔を算出する短時間平均拍動間隔演算手段と、長時間平均拍動間隔を算出する長時間平均拍動間隔演算手段と、短時間平均拍動間隔と長時間平均拍動間隔との差を演算する拍動間隔谷演算手段と、短時間平均拍動間隔と長時間平均拍動間隔との差の時系列のうち、所定の谷深さ閾値Ｖよりも小さい値が存在している箇所を１個の拍動間隔谷と判定する拍動間隔谷判定手段と、所定の判定時間内の拍動間隔谷の数を積算する所定判定時間内谷数積算手段と、拍動間隔谷の数を所定の異常谷数閾値Ｐと比較し、拍動間隔谷の数が異常谷数閾値Ｐ以上ならば無呼吸状態であると判定する谷数比較手段とを備える。【選択図】図１
