The present invention refers to a disposable connector 20 suitable for engagement on the substitution port 180 of a hemofiltration machine 18. The connector 20 comprises: a rigid main body 22 defining a duct 220 and a soft element 24 fitted on an end of the main body 22. In the connector 20 according to the invention, the soft element 24 comprises a membrane 240 occluding the duct 220 and performing a valve function and a seal portion 242 radially expanding outward of the duct 220.
