The invention relates a safety IV catheter assembly comprising a catheter tube having a distal end and a proximal end； a catheter hub having a distal end and a proximal end； a needle extending through the catheter hub and the catheter tube having opposite proximal and distal ends defining an axial direction A, wherein the proximal end is joined to the needle hub and the distal end forms a needle tip and a change in profile is provided between the proximal and distal ends of the needle； and a tip protector assembly being arranged movably on the needle in-between the catheter hub and needle hub outside the catheter hub in an arrangement engaging with one or more second locking means provided on the catheter hub in its ready position, wherein the first arm is deflected radially outwards by the needle against a restoring force, wherein the tip protector assembly is configured to entrap the needle tip upon withdrawal of the needle from the catheter hub.
