Filed experiments were carried out to manufacture an extraction machine from locally available materials suitable for extracting sisal fibers and evaluate its performance under field conditions. The extraction machine (decorticator) performance was conducted under four extracting drum speeds of 7.85, 12.57, 17.28 and 22 m/sec., Three clearances between the knives and the feeding drum of 4, 7and 10 mm, three feeding drum speeds of  0.05, 0.1 and 0.15 m/sec and three different knife number of  2, 3 and 4. Extraction machine (decorticator) performance was evaluated in terms of machine productivity and efficiency, specific energy and operating cost. The experimental results recommended to use the developed machine under the following condition: extracting drum speed of 22 m/sec., clearance of 7 mm, feeding speed of 0.15m/s and 3 knives.