PURPOSE: To provide the titled dope having excellent stability and suitable for use in molding, adding CS2 to an aq. alkaline soln. contg. cellulose.

CONSTITUTION: The temp. of an aq. soln. contg. an alkali (e.g. NaOH) at a concn. of 2W2.5mol/l is adjusted to -12W25°C, and a least 3wt% cellulose having a dgree of polymn. of 700 or below is immersed therein and left to stand for 5min.18hr. The mixture is stirred at 10°C or below to dissolve cellu lose, thus obtaining an aq. alkaline soln. contg. cellulose, 0.01W1.6mol (per glucose residue of cellulose) of CS2 is added to said aq. soln. and the soln. is left to stand at -12W40°C for the least 7 days.