Each year, billions of fired-clay bricks are produced globally, leading to significant environmental concerns due to the energy-intensive manufacturing process. This study explores a sustainable alternative by focusing on the development and performance evaluation of Cement-Stabilized Mud Blocks (CSMB) reinforced with coconut coir and jute fiber. These natural and biodegradable fibers enhance the mechanical properties of CSMBs, making them a viable substitute for conventional burnt clay bricks in construction. Although fired clay bricks are widely used, their production requires high energy input and results in harmful emissions. CSMBs, on the other hand, are more economical and environmentally friendly, though their mechanical performance typically needs improvement. This research investigates whether increasing the proportion of coconut coir and jute fiber can further improve the structural integrity and durability of CSMBs while maintaining sustainable production methods. Blocks were produced with varying ratios of cement and fiber content and tested for compressive strength, water absorption, and efflorescence. Results showed that the optimized mix (CSMB-CC75-JF75) achieved a 147.1% increase in compressive strength and a 22% reduction in water absorption compared to the lowest-performing mix (CSMB-CC15-JF15). These enhancements demonstrate the strong potential of optimized fiber-reinforced CSMBs in sustainable construction. The findings support the use of locally available agricultural fibers to create cost-effective, structurally sound, and environmentally responsible building materials, offering a practical solution to reduce the environmental impact of brick manufacturing.