PURPOSE: To obtain a glass fiber for direct injection molding having high strength and capable of providing a glass fiber-reinforced thermoplastic resin excellent in appearance and quality.

CONSTITUTION: This glass fiber for direct injection molding is a glass fiber whose surface is treated with a polyether type urethane resin so that an amount of the resin attached is ≥1.0wt.%. The glass fiber for direct injection molding is obtained by using the polyether type urethane resin as a part of a collecting agent in a form of emulsion or an aqueous solution formed by introducing a hydrophilic group in a part of the resin and applying the resin to the surface of the glass fiber. A polyether type urethane resin obtained by reacting a diisocyanate with a polyether polyol is preferably used as the polyether type urethane resin. A glass fiber having 3-25μm diameter is preferably used as the glass fiber.