Effective project scheduling is crucial in project management to ensure timely completion and minimize the risk of delays. This study analyzes project scheduling using the Critical Path Method (CPM) for the Dismantle and Erection Spherical Tank project by PT. Rekabangun Energi Nusantara. Data was obtained through field observations, interviews, and project documents. By applying the CPM method using Microsoft Project, the project’s initial duration of 110 days was optimized to 98 days, achieving a 10.9% time efficiency with a 12-day reduction in project duration. The project’s critical path includes key activities such as Work Permit and HSE Plan, Dismantle Work, and Erection and Welding Work. Progress monitoring was conducted using the Curve-S graph to compare actual progress against the planned baseline. Resource efficiency was achieved by optimizing the workforce in the welding and rigging sections and improving the effectiveness of heavy equipment usage, such as cranes and generato