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The [La.sub.0.8][Ca.sub.0.2][Mn.sub.0.99][sup.57][Fe.sub.0.01][O.sub.3] sample was prepared by sol-gel method. The crystallographic and magnetic properties of [La.sub.0.8][Ca.sub.0.2][Mn.sub.0.99][sup.57][Fe.sub.0.01][O.sub.3] have been studied using x-ray diffraction (XRD), vibrating sample magnetometer (VSM) and Mossbauer spectroscopy measurements. The crystal structure of [La.sub.0.8][Ca.sub.0.2][Mn.sub.0.99][sup.57][Fe.sub.0.01][O.sub.3] was found to be orthorhombic (Pnma) structure with lattice constants [a.sub.o] = 5.486 [Angstrom], [b.sub.o] = 7.761 [Angstrom], and [c.sub.o] = 5.510 [Angstrom] at room temperature. The Curie temperature ([T.sub.c]) is determined to be 160 K by zero field coolded (ZFC) magnetization curve under 5 kOe applied field. The maximum value of magnetic entropy changes, [absolute value of [DELTA][S.sub.M]] is 1.25 J/kg x K at 157 K under 13 kOe applied field. Mossbauer spectrum at 4.2 K was fitted with two independent magnetic components of the magnetic hyperfine fields [H.sub.f,1] = 526 kOe and [H.sub.f,2] = 501 kOe. Mossbauer spectra show that the two well-resolved sextets show nearly equal intensities between them without any external fields. This unusual phenomenon provides direct evidence of the two-phase character of the metallic state in the mixed valence state of [La.sub.0.8][Ca.sub.0.2][Mn.sub.0.99][sup.57][Fe.sub.0.01][O.sub.3] powder. Index Terms--[La.sub.0.8][Ca.sub.0.2][Mn.sub.0.99][sup.57][Fe.sub.0.01][O.sub.3], magnetic refrigeration, magnetocaloric effect, Mossbauer spectra, sol-gel method.