The effect of fiber length on the mechanical properties of sisal fibre reinforced unsaturated polyester composite has been investigated. Sisal fiber was extracted from sisal leaves by water retting method. The fibers are chemically treated in 5% NaOH solution for 1 hour at room temperature. The composites are prepared by hand lay-up technique with random fiber orientations of different length(20mm,35mm &50mm) and constant volume fractions(10wt%). Computerized universal testing machine was used to test the tensile and flexural test, while izod impact testing machine was used for the impact test. Experimental results show that the tensile strength, flexural strength and impact strength are increased with increasing fiber length. The 50mm fiber length composite exhibited the maximum tensile strength, flexural strength and impact strength compared to the other fiber length used in the composites.
