The experimental bifurcation analysis of the electrochemical steady state and oscillatory behaviour of the Fe/14.8M H3PO4 system is studied by using as control parameters the applied potential, the Fe-disc rotation speed and an external resistance. The external resistance was inserted in series between the ground and the Fe-disc electrode. At T = 298 K and dE/dt less-than 10 mV s(-1) four stable potential regions can be distinguished in the current-potential (I-E) curve : the active, the peak current, the plateau limiting current and the passive regions. Increase of the potential scan rate, and the Fe-disc rotation speed, as well as decrease of the temperature and the phosphoric acid concentration, all induce an oscillatory region in the I-E curve. The oscillatory region is located across the transition from the passive state to an active one observed during the backward potential scan. The factors destabilising the system are all associated with an increase of the ohmic potential drop during polarization. Addition of an external resistance between the ground and the Fe-disc electrode confirms the effect of the ohmic potential drop on the stability of the Fe/H3PO4 system. The current oscillations induced by varying either the external resistance or the Fe-disc rotation speed are periodic of a relaxation type. By varying the phosphoric acid concentration, complex (mixed-mode) oscillations are observed as well. On the basis of the experimental findings, a supercritical Hopf bifurcation and a saddle-node of infinite period bifurcation seem to occur close to the critical potentials of the oscillation onset from the active and passive state, respectively.