Polydimethylsiloxane (PDMS) adhesive films have increasingly attracted attention due to their inherent properties such as biocompatibility, high flexibility, optical transparency, and many others. In this contribution, dopamine-functionalized polydimethylsiloxane polymer conetworks prepared from poly(pentafluorophenyl acrylate)-l-polydimethylsiloxane (PFPA-l-PDMS) amphiphilic polymer conetwork precursors are proposed. This straightforward approach gives easy access to polydopamine-functionalized PDMS polymer conetworks with a different composition, stiffness of the polymer conetwork, and their corresponding nanoscale phase-separated morphologies. The adhesive property of the polymer films on the glass substrate obtained by lap shear testing gives a maximum adhesive strength of 0.85 ± 0.08 MPa thanks to phase-separated morphologies at the nanometer scale and the high flexibility inherent to polysiloxane. The proposed approach provides an easy and straightforward way to introduce dopamine into a polymer conetwork with tunable adhesive properties.