Alkali soluble resin, manufacturing method of the same and emulsion polymer including alkali soluble resin

Provided are: an alkaline water soluble resin; a method for producing an alkaline water soluble resin; and an emulsion polymer including an alkaline water soluble resin. The alkaline water soluble resin is produced by polymerizing a first monomer which includes one or more among an acrylic monomer, a methacrylic monomer, or a styrene-based monomer and does not have an allyl group, and a second monomer which has an allyl group. The alkaline water soluble resin according to an embodiment of the present invention has a high weight-average molecular weight and has a relatively low viscosity of an alkaline water soluble resin solution when dissolved in an alkaline medium, thereby exhibiting excellent polymerization properties and outstanding durability such as chemical resistance or water resistance.