Thin films of iron diselenide (FeSe2) were electrodeposited on tin oxide coated conducting glass substrates at various bath temperatures. The deposited films were characterized by X-ray diffraction (XRD), optical, energy dispersive analysis of X-rays (EDAX) and scanning electron microscopy (SEM). The structure was found to be orthorhombic with preferential orientation along [1 2 1] plane. X-ray line profile analysis technique by the method of variance has been used to evaluate the microstructural parameters. Various microstructural parameters such as, crystallite size, rms strain, dislocation density and stacking fault probability affecting the fraction of planes with film thickness and bath temperatures were studied. The experimental observations are discussed in detail. (c) 2007 Published by Elsevier B.V.