A plasma wind tunnel has been constructed and the super‐Alfve´nic flow over a magnetic obstacle studied. The wind tunnel produces a steady (10−3sec) flow of high enthalpy (∼100 eV), high density (1014) plasma. The flow of this high conductivity plasma has been studied using magnetic field probes. The interface and shock wave produced in front of a magnetic obstacle in the flow have been studied. The shock wave is shown to satisfy the usual magnetohydrodynamic Rankine—Hugoniot relations.