A locking cannula for medical lines comprising a tubular body (1) having a cannula appendage (2) extending axially therefrom, and a pair of elongated anchoring wings (3) arranged on opposite sides of the body (1) and including respective manoeuvring parts (4) and respective engagement parts (5). The anchoring wings (3) are connected to the body (1), between said manoeuvring parts (4) and said engagement parts (5), through respective elastically deformable arms (7), which each have a first portion (11) joined to the body (1), which is obliquely orientated to the side of the cannula appendage (2), and a second portion (12) joined to the engagement parts (5) of the respective anchoring wing (3), which is essentially orientated parallel thereto.
