The ferroelectric and magnetic properties and the magnetoelectric coupling (MEC) effects of Pb(Fe0.5Nb0.5)O3 (PFN) thin films grown on SrRuO3/Si substrates by the radiofrequency (RF) magnetron sputtering technique were studied. Highly textured, single-phase films with [110] preferential orientation and different thicknesses were successfully grown. Electric (P–E) hysteresis loops showed excellent and almost constant values of the maximum (∼65μCcm−2) and remanent (∼25μCcm−2) polarizations from 4K to room temperature. Ferromagnetic order in the low-temperature region (below 50K) is reported for the first time in PFN and discussed. The maximum (∼3emug−1) and remanent (∼1.5emug−1) magnetization values were obtained. Magnetic field dependence of the ferroelectric hysteresis loops was investigated for temperatures of between 4 and 100K. Coexistence of ferroelectricity, magnetism and spin crossover phenomena were observed, and a significant direct DC MEC effect expressed by the coefficient α=ΔPr/ΔH with maximum value of 120pCcm−2Oe−1 at 4K is reported.