A splittable conjugate fiber comprising a polyester segment and a polyolefin segment, wherein the splittable conjugate fiber comprises two or more parts of the polyester segment extending from a center of the fiber toward an outer edge of the fiber in a cross-sectional configuration perpendicular to its longitudinal direction, in which at least one of the two or more parts of the polyester segment extending from the center of the fiber toward the outer edge of the fiber is exposed at the outer edge of the fiber and at least one of the two or more parts of the polyester segment extending from the center of the fiber toward the outer edge of the fiber is unexposed at the outer edge of the fiber.