Abstract— The mechanical properties of cement bonded fibreboards theoretically influenced by several factors like density, water cement ratio, fibre to cement ratio and geometry of fibre has been discussed by previous researchers. This experimental research work was conducted to explore the role of EFB Fibre geometry on the mechanical performances of cement boards. The experiment work designed for 1300 Kg/m³ density boards consist of two parts, first is cement boards mixed with different length of EFB; retained 7 mesh (R7M), retain 14 mesh (R14M) and retain 80 mesh (R80M). Subsequently, second part is based on the cement boards fabricated from mixed of 6 different percentage lengths of EFB known as SA, SB, SC, SD, SE and SF. The ratio of EFB to cement was 3:1, while water used in the system was 35% based on cement weight. To improve the compatibility of EFB-cement, the fibres were soaked in 0.4% NaOH solution for 24 hours. The mechanical properties were investigated in this study like modulus of elasticity (MOE), modulus of rupture (MOR) and internal bonding (IB). It was observed that the higher presence of shorter EFB (R80M) in cement boards, the lower mechanical properties were produced. The boards fabricated with heterogeneous fibre length, SE (35% R7M + 45% R14M + 20% R80M) produced the highest mechanical properties with MOE of 4859.5 N/mm², MOR of 10.06 N/mm² and IB of 0.36 N/mm². The properties of MOE and MOR for boards fabricated from SE mixture were satisfy the minimum requirement of British standard.