Abstract: The study investigated the relationship between principal’s supervisory strategies and teacher’s instructional performance in terms of some variables such as teaching materials and discipline maintenance. The population comprised all the 192 principals and 3492 teachers in Delta north senatorial district. Two null hypotheses were formulated to guide the study and tested at alpha level of significance of 0.05. The multi-stage sampling technique was used to select 92 principals and 349 teachers. The face and content validity of the instrument (questionnaire) was established and the reliability coefficient^® value was 0.78 showing that the instrument was reliable. The data collected was analyzed using the Chi-square statistical tool, the results revealed that there was a significant relationship between principal’s performance with regards to teaching materials and discipline maintenance based on the findings and conclusion, it was recommended that adequate fetching materials should be provide for teachers effectiveness in the teaching-learning process.