Positive instructional supervision is the key to improve teaching and learning. The purpose of this study is to analyze the concepts of positive instructional supervision, correlation between positive instructional supervision and teaching effectiveness and exploring the strategy of how to utilize positive instructional supervision to enhance teaching effectiveness. Positive instructional supervision has its origin from positive psychology, which demonstrates the process of building rapport, goal formulation, finding competencies and exceptions, work progress, reflection and feedback, as well as followup session. In addition, correlation exists between positive instructional supervision and teaching effectiveness. The researchers propose strategies of how the mentor teachers use positive instructional supervision to enhance teaching effectiveness of mentees as follows: (1) Collaboratively establishing stretch goals and guiding continuously the improvement of teaching; (2) Making good use of the strengths of mentees to promote positive energy and results; (3) Using positive questioning skills to encourage self-directed teaching improvement; (4) Inspiring mentees to reflect and feedback to strengthen the mentoring effectiveness; (5) Combining collaborative lesson planning, lesson observing and discussions to improve effectiveness of positive instructional supervision; (6) Actively developing models specific to local communities and constructing differentiated positive supervision.