The background of this research is the existence of problem on whether the implementation of Occupational Safety and Health (OSH) in the project of Cilacap Expansion 1x1000 MW CFSPP has been in accordance with the standard operation procedure (SOP) of the company. PT Wijaya Karya as the contractor of the project is committed to the protection of their workforces from occupational accident by referring to the SOP of OSH of the company. It is in order to know whether the implementation of OSH has been in line with the SOP issued by the company. The implementation of OSH must be taken into account and applied by all workforces in order to prevent the occupational accident. This is a descriptive research with cross sectional approach. Questionnaires are distributed to 110 labors in the work of concrete formation. The data obtained from questionnaires are analyzed using SPSS2010 and Microsoft Excel. The findings show that the implementation of OSH in the project of Cilacap Expansion 1x1000 MW CFSPP has been mostly in line with the SOP of the company (81.7%). The findings are supported by the factors of top management (87.2%), communication among workforces (79.3%), occupational safety (95%), occupational health (85.7%), occupational environment (84.3%), occupational discipline (79.5%), and the performance of the workforces (62.1%).