The Quality Assessment System in Construction (QLASSIC) developed by CIDB to measure and evaluate the quality of workmanship and finishes of construction works. Unfortunately, QLASSIC is not fully implemented and applied by all contractors in Malaysia as this element is not a compulsory requirement in getting projects. This paper presents the findings of determination on the understanding of contractors towards the implementation of Quality Assessment System in construction (QLASSIC) in construction industry. This objective was achieved based on the literature review and questionnaire survey. The respondents were selected based on the grade of contractor from G5 to G7 construction companies in Klang Valley. Sample of questionnaire would be 200 and the reply from respondents responded is 95. The data was analysed using Reliability Analysis and Descriptive Analysis. The results indicate that the understanding of contractors is only basic understanding on QLASSIC system but the detail implementation of QLASSIC from contractors were still low. On further research, it may able to study on the implementation of QLASSIC in client’s perspective. The research will study on the implementation of QLASSIC but in the others perspective which is look into the understanding of QLASSIC to clients, the challenges and benefit from QLASSIC implementation.