Mediated communication technologies, conveying verbal and nonverbal cues, are more and more employed in learning activities. Nevertheless, their effects on teacher-student interaction have been not clearly stated yet. Through two experimental studies, we investigated on the effects of nonverbal communication cues (kinesic and ostensive-inferential) on synchronous mediated tutoring dialogue, in which a tutor and a student communicate through audio-video communication tools. The outcomes show that kinesic cues lead tutor to monitor more carefully learner’s ongoing task and to encourage much more them, while ostensive-inferential cues improve learner’s task performance and lead both tutor and student to focus better on tutoring speech acts.