The present invention relates to a syringe, and more particularly, to an apparatus obtained by improving an conventional syringe formed with an injection flow passage including an injection needle, so as to share a portion of the injection flow passage except the injection needle or to form a suction flow passage completely independent of the injection flow passage, thereby further smoothing suction of a liquid medicine. The syringe is configured such that the separate suction flow passage bypassing the injection needle is formed in an conventional syringe to more smoothly perform the suction of the liquid medicine, thereby maximizing users convenience and marketability of the product.