This study is to confirm significant group determination for life logging. Six undergraduate students were participated in experiment. They were divided to two groups consist of three persons. Subjects were presented to sixteen movie clips relating to emotion of four categories. PPIs (Pulse to Pulse Intervals) extracted from PPG were analyzed. Pearson correlation was tested to PPIs between subjects. When the same emotional stimuli were presented, PPIs of twelve pairs were highly correlated significantly. These results showed the possibility to utilize criteria for synchrony for determining significant group.