To provide a binder resin composition keeping good low-temperature fluidity and coated film performance and being inexpensive.

The binder resin solution composition comprises (a) a resin obtained by mixing a chlorinated polyolefin (I) obtained by chlorinating an isotactic polypropylene-based polymer produced in the presence of a metallocene catalyst, having ≤3 molecular weight distribution and having 110-140°C melting point measured by a differential scanning type calorimeter to 10-40 wt.% chlorine content with a carboxy group-containing chlorinated polyolefin (II) obtained by chlorinating a carboxy group-containing polyolefin obtained by grafting isotactic polypropylene-based polymer produced by using a titanium-based catalyst with 1-10 wt.% at least one kind of unsaturated carboxylic acid monomer selected from a carboxylic acid and a carboxylic acid anhydride in a weight ratio (I/II) of (5/95) to (50/50) and (b) an organic solvent, and the binder resin solution composition has 10-50 wt.% solid content concentration.