The study aims to investigate the influence of the supervisory styles on supervision outcome among undergraduate counsellor trainees. Empirical gap and methodological gap are delivered through this study by considering Malaysian context as the background of the study and taking undergraduate population with heterogeneous sample involved. System Approach to Supervision (SAS) Model serves as the basis to carry out the study. This study is quantitative in nature with correlational research design to study both the influence and relationship between supervisory styles and supervision outcome (counsellor trainees’ satisfaction). The pilot study involved 30 students from the Bachelor of Counselling (Honors) program at UNIMAS who are undergoing their practicum training. Stratified random sampling technique is utilized to select the respondents. The Supervisory Style Inventory (SSI) instrument measures three subscales (attractive, interpersonally-sensitive and task-oriented style). The three subscales have reported high reliability analysis. The result showed that SSI has a high reliability analysis ranging from α = 0.868 to α = 0.924. The reliability values of the three subscales are reported respectively as follows: (i)attractive at α = 0.92; (ii) interpersonally-sensitive α = 0.87; and (iii) task-oriented α = 0.92. The SSI instrument is reliable for measuring the supervisory styles of supervisors towards supervisees. Implications of the findings for counsellors, supervisors, trainee counsellors and area for future research are discussed with regard to attractive, interpersonally-sensitive and task-oriented.