Catheter insertion device, comprising a catheter hub (1) at the proximal end of a catheter (Ia), a tubular needle hub (4), at which a hollow needle (5) is fixed which extends through the catheter hub and the catheter (Ia) in a ready position such that the needle tip (5.1) projects over the distal end of the catheter (Ia), a protective barrel (3) which is received in the tubular needle hub (4) in the ready position and is releasably connected to the catheter hub (1), and a pressure spring (6) arranged between the needle hub (4) and the protective barrel (3) and which displaces the needle hub (4) and the protective barrel (3) apart from each other in axial direction, wherein a manually operable holding member (3.5) is provided between the needle hub (4) and the protective barrel (3), and holds the needle hub (4) in the ready position at the protective barrel (3) against the bias of the pressure spring (6), so that after the holding member (3.5) is released, the pressure spring (6) moves the needle hub (4) into a protective position in relation to the protective barrel (3), in which position the needle is positioned in the protective barrel (3).Linvention porte sur un dispositif dinsertion de cathéter, comprenant une embase de cathéter (1) au niveau de lextrémité proximale dun cathéter (Ia), un raccord daiguille tubulaire (4), auquel est fixée une aiguille creuse (5) sétendant à travers lembase de cathéter et le cathéter (Ia) dans une position dattente de telle sorte que la pointe de laiguille (5.1) fait saillie sur lextrémité distale du cathéter (Ia), un tube protecteur (3) reçu dans le raccord daiguille tubulaire (4) dans la position dattente et relié de manière libérable à lembase de cathéter (1), et un ressort de pression (6) disposé entre le raccord daiguille (4) et le tube protecteur (3) et déplaçant le raccord daiguille (4) et le tube protecteur (3) en les écartant lun de lautre dans la direction axiale, un élément de maintien pouvant être actionné manuellement