This quasi-experimental study sought to investigate the effects of instructor verbal and nonverbal immediacy behaviours on studentsā€˜ communication (i.e., class participation) and learning outcomes (i.e., state motivation, communication satisfaction, affective learning, and cognitive learning). The study sampled 115 undergraduate students at King Khalid University in Saudi Arabia. The participants were distributed into three groups: two control groups and one treatment group. The current study combined a quantitative method using a survey with a qualitative method using a semi-structured interview design. In this study, students participants completed the same survey at two different times: pre-test and post-test. Instrument measurements were composed of seven elements: verbal immediacy, nonverbal immediacy, class participation, state motivation, communication satisfaction, affective learning, and cognitive learning. The findings of this study strengthen that generally, instructor verbal and nonverbal immediacy behaviours cause positive student communication and learning outcomes. However, nonverbal immediacy was not shown to affect cognitive learning. These findings illustrate the predominance of verbal immediacy over nonverbal immediacy. The results are discussed and implications are given for instructors and administrators at various universities in Saudi Arabia. Instructor immediacy appears to be a significant factor in developing interpersonal relationships with students and promoting student communication and learning outcomes.