A communication skill evaluation system including: an audio input device; a measurement device; an utterance period detection unit that, based on the audio information input by the audio input device, detects an utterance period and a participant who spoke in each utterance period; a participatory role assignment unit that assigns a participatory role to each participant in accordance with whether or not each participant spoke in each utterance pair composed of two utterances obtained in chronological order from each utterance period; a feature quantity extraction unit that, based on the measurement results by the measurement device, extracts a non-verbal feature quantity for each participant, relating to the non-verbal action at the end of the utterance in each utterance period; and an estimation unit that estimates communication skill for each participant based on a combination, in each utterance period, of the participatory role and the non-verbal feature quantity.