To obtain a fiber for a polarization woven fabric which has excellent durability, such as high temp. and high humidity resistance and UV resistance, and withstands severe conditions without degrading its polarization characteristics by using a fluorine polymer contg. a UV absorbent as a sheath component.

The polymer constituting the core component of the polarization composite fiber includes polyester and ethylene vinyl-alcohol copolymer having a cobwebbing property and transparency. The polarized light developable material to be incorporated into the core component is preferably org. dichromatic dyestuff and the dyestuff is preferably a hydrophilic direct dye. The fluorine polymer constituting the sheath component is preferably polyvinylidene fluoride as this polymer is easily melt spinnable with the polymer which is the core component. The sheath component contains the UV absorbent. The UV absorbent is preferably the absorbent which does not hinder the ray transmittability of the fluorine polymer. The content thereof is preferably 0.1 to 5.0wt.% of the fluorine polymer.