Abstract Four Eu-Sr manganites, La 0.7-x Eu x Sr 0.3 MnO 3; x= 0.4, 0.5, 0.6, 0.7, and one Nd-Sr manganite Nd 0.4 La 0.3 Sr 0.3 MnO 3, were studied by EPR (electron paramagnetic resonance) at 9.6 GHz at temperatures in the range 175–400 K. These studies were further supplemented by magnetization measurements. The positions and widths of the EPR lines of all the Eu-Sr manganite samples, containing Eu 3+ ions, changed with temperature in a similar manner. The EPR data showed that these Eu-Sr manganites are ferromagnetic, whose magnetic transition temperature from the ferromagnetic to the paramagnetic state (T C) decreased gradually as the Eu content (x) increased, specifically from T C~ 111 K (x= 0.5) to T C~ 57 K (x= 0.7). Furthermore, in these samples the FMR (ferromagnetic resonance) lines appeared significantly above the respective T C, specifically, at 290 K (x= 0.4), 280 K (x= 0.5), 250 K (x= 0.6), together with the EPR lines. As for the sample with x= 0.7 no FMR lines were observed in the temperature range investigated here. The temperature dependence of the EPR linewidth is found to be linear in the various La 0.7-x Eu x Sr 0.3 MnO 3 samples, caused by the presence of conductivity due to small-polaron hopping The peak-to-peak first-derivative EPR linewidths, ΔB pp, of these Eu-doped samples fitted well above the temperature, at which the minimum of ΔB pp occurs, to the expression: ΔB pp (T)= ΔB pp, min+ A T exp (-E a/k B T), with the values of the activation energies being E a= 0.20 eV, 0.17 eV, 0.11 eV, 0.09 eV for x= 0.4, 0.5, 0.6, 0.7, respectively. On the other hand, for the Nd-doped sample, the ΔB pp in Nd 0.4 La 0.3 Sr 0.3 MnO 3 decreased monotonically with temperature above T C in accordance with the Curie-Weiss law as ΔB pp (T)= ΔB pp, 0+ C/(TT C). The magnetization measurements were exploited to determine T C for the various samples. The results agreed with those determined by the EPR measurements presented here. In addition, the magnetization data was analyzed to obtain the values of the critical exponents in the phase transition from the paramagnetic to the ferromagnetic state. The critical exponents, as determined for the La 0.7-x Eu x Sr 0.3 MnO 3 sample with x= 0.5, are β= 0.24±0.02, γ= 1.10±0.5, δ= 5.58.