The aim of this work is to associate the main technological properties of flax fibers with a developed machine prototype. The determined results are necessary as a database to develop a simple machine for helping the Egyptian farmers in the process of flax fiber separation. A proper prototype was fabricated at a locally workshop at Meet-Ali, Dakahleia Governorate. The determined technological properties of long flax fibers were:- fiber percentage, fiber length categories,  fiber fineness, and fiber strength. These properties were investigated as affected by different machinery, and crop variables such as: separating drum speed (of 1.58, 3.52 and 8.21 m/s), straw feeding rate (of 2.0, 2.5 and 3.0 kg/ min)., and straw moisture content (of 8.42, 10.8 and 12.6 %,wb). The gained results reveled that; -      The best performance of the developed machine prototype, with respect to long fiber percentage (14.32%),and to fiber length category(78.99 cm) were obtained at drum speed of 1.58 m/s, feeding rate of 120 kg/hr and straw moisture content of 8.42%.   -     The best degree of fiber fineness (129.74 mm / mg) was accomplished drum speed of 8.21 m/s, feeding rate of 120 kg/hr and straw moisture content of 8.42%. While, the best fiber strength (27.14 tex /gr ),was associated with drum speed of 1.58 m/s feeding rate of 180 kg/hr and straw moisture content of 12.6%.