PROBLEM TO BE SOLVED: To provide a needle guard mechanism for protecting a user and another person from the sharpened tip of a needle after drawn out of a patient.SOLUTION: This invention is a safe catheter device equipped with a catheter hub (220) and a catheter tube (226) a needle hub (208) and a needle (52), a needle guard constituted so as to be capable of transferring the needle over a needle first state wherein the tip of the needle is not protected and a needle second state wherein the tip of the needle is protected, the separable shroud (320) provided in relation to the needle hub and a sheath (370) surrounding at least the catheter tube and the needle tip and positioned with respect to at least a part of the separable shroud.