The development of construction industry in Indonesia has been substantially contributing to the enhancement of social and economy of the country. However, its expansion may also give negative effects to the environment if the practices of implementing the construction project neglected the rules and regulations of sustainable construction concept. The aim of this study is to develop Green Construction Site Index (GCSI) with the consideration of assessing the staff commitment level on the implementation of the sustainable construction practices. Therefore, Project Organizational Commitment Index (POCI) is also developed. Data were collected by on site direct observation, distribution of questionnaire and interview with key personnel and project documentation review. All the data were tabulated and analyzed by using descriptive elaboration method. The development of GCSI and POCI was based on the opinion and validation of selective experts in the importance of sustainable elements in construction by using Average Index Analysis. Evaluations of GCSI and POCI have been conducted toward ten selected construction projects in Indonesia. The findings have revealed that the overall GCSI value of all ten construction projects was 3.39 which indicated that level of sustainability was in a good category. Meanwhile, the POCI value of all the projects was 3.31 showing that the commitment level of staffs in implementing the sustainable construction project practices was also in a good category. The result shows and proves that the establishment of GCSI and POCI were able to be used to assess level of sustainability construction project in the perspective of project progress and level of staff commitment. It shows that the capability of GCSI and POCI in assessing level of sustainability construction project, based on sustainability concept of construction project. In conclusions, GCSI and POCI are beneficial and suitable to be used in measuring level of sustainability in construction project by respective construction stakeholders like government bodies, local authorities and contractor
