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Abstract: We present electron paramagnetic resonance (EPR)—evidence of photomagnetism under the conditions of in situ green laser illumination (photo-EPR) in lead magnesium niobate–lead titanate, Pb(Mg,Nb)O3–PbTiO3 (PMN–PT), containing nanoparticles/wires of orthorhombic β-PbO as identified by Raman spectroscopy. Photo-EPR studies of the sample containing β-PbO, brownish red in color, have shown intense line at g =2.00, and its yield increased when produced in the presence of 7.5kG external magnetic field suggesting the formation of magnetic polaron. This was identified as due to interaction between Fe3+, photoinduced Pb3+ and unpaired electron trapped at oxygen vacancies. The photoinduced growth and decay of magnetic polaron has shown a non-exponential behavior. Photoluminescence (PL) studies were conducted with excitation at 308nm (XeCl laser) and also at 454.5, 488 and 514.5nm using Ar+ laser. The excitation with 308nm gave broad PL centered at 500 and 710nm the latter being quite prominent in β-PbO containing crystals, along with cooperative luminescence at 350nm involving two emitting centers. The excitation with Ar+ laser lines, close to the electronic absorption in samples containing β-PbO gave richer and sharp PL emission in red region from the constituents of the magnetic polaron and also intense anti-Stokes emission on excitation with 514.5nm radiation. This appears to be due to phototransfer optically stimulated luminescence (PT-OSL) involving electron–hole recombination at photoinduced magnetic polaron site. [Copyright &y& Elsevier]