Hybrid composite boards were manufactured from oil palm trunk (OPT), frond (OPF), empty fruit bunch (EFB) and polyethylene. Four different plastics content of 0%, 5%, 12% and 20% were used in this study. The boards were manufactured to target density of 850 kg m^-3. Urea formaldehyde (UF) adhesive was used as a binder at resin level of 10%. The properties of the resultant boards were determined according to the Japanese Industrial Standard (JIS-A-5906, 1983). All the OPF boards and all the other boards with 5% and 12% plastic content irrespective of the fibre types satisfied the 200-type board for modulus of rupture as stated in the JIS-A-5906. The OPT boards and all other boards with 0% and 20% plastic content passed the JIS-A-5906 150-type board while the EFB boards only passed the JIS-A-5906 50-type board. For internal bonding (IB), all the boards were able to meet the requirement of JIS-A-5906 300-type board. In the case of thickness swelling (TS), all the boards failed to meet the requirement as specified in the JIS-A-5906 standard. However, the dimensional stability of the boards increased with increased quantity of plastic used.