Uraki et. obtained organosolv lignin (AWL) by reacting birch wood with acetic acid. Then two different thermal treatments were done on the obtained lignin to enhance the spinnability. The first one involved heating samples for 30 minutes at 130°C and 160°C under reduced pressure; the resulting samples were designated 130-AWL and 160-AWL, respectively. In the second one, AWL was prespun at 210°C using the nozzle, with three holes to yield the thick and short fibers. A considerable difference was observed in the pretreated fibers. The 160 AWL and prespun AWL showed enhanced spinnability. The resultant precursor fiber was smooth with some micropores. On the other hand, the spinnability did not significantly improve for 130-AWL. The pretreated AWL was subjected to melt spinning at 210°C at a spinning rate greater than 400 m/min. Then, the thermosatbilization was done at 250°C at a 0.5°C/min rate and finally, carbonized at 1000°C at 3°C/min. Excellent mechanical properties were possessed by the resulting carbon fibers. These characteristics are comparable to carbon fibers made from steam-exploded phenolated lignin. The general performance grade carbon fibers can be procured from AWL.