The present disclosure relates to a process for preparing alkali metal salt of carboxyalkyl ether of tamarind gum with one or more improved properties like improved viscosities and electrolytic stability. Particularly the present disclosure provides a process for preparing alkali metal salt of carboxyalkyl ether of tamarind gum comprising: (a) permeating a pulverized tamarind gum powder by mercerizing said pulverized tamarind gum powder in the presence of an alkali, and a non-aqueous organic polar solvent present in an amount of at least 2 times the amount of the tamarind gum v/w; (b) carrying out etherification of alkali-tamarind gum with etherifying agent to provide an alkali metal salt of carboxyalkyl ether of tamarind gum; in which, steps of mercerizing the pulverized tamarind gum powder and etherification are carried out separately or simultaneously.