In this article, mechanical performance of isothalic polyester-based untreated woven jute-fabric composites subjected to various types of loading has been experimentally investigated. The laminates were prepared by hand lay-up technique in a mold. Specimens for tests were fabricated as per ASTM standards. All the tests (except impact) were conducted on closed loop servo hydraulic MTS 810 material test system using data acquisition software Test Works-II. From the results obtained, it was found that the tensile strength and tensile modulus of jute-fabric composite are 83.96% and 118.97% greater than the tensile strength and modulus of unreinforced resin, respectively. The results of other properties, such as flexural, in-plane shear, interlaminar shear, impact, etc., also revealed that the isothalic-polyester-based jute-fabric composite have good mechanical properties and can be a potential material for use in medium load-bearing applications. The failure mechanism and fiber-matrix adhesion were analyzed by scanning electron microscope. Effects of long-term immersion in water on mechanical properties are also presented. (c) 2007 Wiley Periodicals, Inc.