Composite boards, using mixture of sawdust from pine (Pinus caribaea M.) and coconut husk or coir (Cocos nucifera L.) a by-product from processed agricultural crop at different mixing ratios with Portland cement as binder were produced for this study. The boards were tested for water absorption, thickness swelling, dry Moduli of rupture and elasticity and density in accordance with ASTM D 1037 (1998). The water resistance, strength properties and density measured possessed higher values in boards with high cement component but were inconsistently lowered with increased inclusion of coir in the different mixing ratios. Although, the two-way analyses of variance values revealed that there was significant variation in the pooled data for all the properties measured, it also revealed that there was no significant variation in the data obtained for all of them at the two cement inclusion levels for each sawdust/coir mixing ratio. Keywords: Pinus caribaea, Cocos nucifera, sawdust, coconut husks, cement-bonding, particleboard, modulus of rupture, elasticity, density.