During clinical practice in hospital, several evaluation method were adopt to support student achieve their competency. Mini Clinical Evaluation Exercise (MiniCEX) is a Workplace-Based Assessment (WPBA) that requires the examiner to observe the student performing a focused task within 15–20 minutes at the clinic or ward with compulsory immediate feedback. This study aim to identify the differencies of selfeffficacy after implemention mini-CEX amongmidwifery students. The design of this study was quasi experiment design with control group. This study were consist of 2 group, 32 students were an intervention group and 30 students were control group. The total sampling applied to get the sample who met with inclusion criteria. General Selfefficacy was applied to measure mean score of self-efficacy. The study found the selfefficacy among both group before implementation mini-CEX were low. However, this study found differences of self-efficacy before and after mini-CEX (11.40). The t-test analyzed shows the mini-CEX was significant effective improving self-efficacy (p value: 0.000). In conclusion the implementation mini-CEX was effective to improve selfefficacy among midwifery student during clinical practice. The Mini-CEXcould be effective assessment method for improving the self-effiacy of students.