In this work, sandwich composite properties were investigated by addition of coconut coir (CC). Fibres in the polyurethane foam cores ranges from 0 to 20 wt.%. Glass fibre reinforced epoxy panels were used as a skin and polyurethane foam as a core, these materials adhesively bonded to keep the whole structure attached with each other. Sandwich composite skins and core-skin bonding were attained via adhesive bonding technique. While polyurethane foam reinforced by coconut coir fibres were manufactured by using one shot process and polyurethane moulding method. Sandwich composite panels with different coir fibres compositions were subjected to the density test, weight per area test and flexural testing in order to investigate their physical and mechanical properties. From the experimental results and analysis, it was found that the sandwich composites with 10 wt.% of coir fibres offer higher mechanical properties.