A tossa variety of jute fiber (Corchorus olitorious) treated with soapglycerol micelles is characterized by infrared (IR) spectroscopy, X-ray diffraction method, and tensilometry. The IR spectra for jute fibers treated with soap-glycerol micelles show a reduced absorption band due to OOH stretching at a frequency of 3420 cm Ϫ1 with almost absent OH bending frequencies, prominent CH 2 stretching and bending frequencies at 2915 and 1440 cm Ϫ1 and reduced skeletal vibration at 1060 cm Ϫ1 . The percentage crystallinity measured by the X-ray diffraction method increases from 45 to 53% on treated jute fibers. The tensile strength and strain percent at maximum load, Young's modulus, and work done per unit volume within an elastic limit (resilience) for treated fibers increased from 1.8 Ϯ 0.2 to 3.43 Ϯ 0.2 GPa, from 3.98 Ϯ 0.1 to 4.75 Ϯ 0.1, from 75 Ϯ 2 to 113 Ϯ 5 GPa, and from 26 Ϯ 2 to 74 Ϯ 3 MJ m Ϫ3 , respectively. Using a stabilizing agent (2%) and a swelling agent (2% KOH), the tensile strength, strain percent, Young's modulus, and resilience increase to 4.02 Ϯ 0.2 GPa, 4.85 Ϯ 0.3, 154 Ϯ 5 GPa, and 95 Ϯ 4 MJ m Ϫ3 , respectively. Under natural weathering at 12-30°C and 30 -80% relative humidity over a prolonged period of 8 weeks, all the tensile properties for micelle-treated fibers increase during the first 2 weeks of exposure and then decrease exponentially to the starting values.