In the present investigation n-type MoBi2(Se1-xTex)(5) nanocrystalline thin films with various compositions of Se and Te were successfully deposited on ultrasonically cleaned glass substrates using recently developed Arrested Precipitation Technique (APT). The effect of composition on optical, morphological, structural, electrical and thermocooling properties of MoBi2(Se1-xTex)(5) were investigated using UV-vis-NIR Spectroscopy, scanning electron microscopy, energy dispersive spectroscopy, X-ray diffractometer, thermoelectric power and thermocooling measurements. Thermoelectric properties including electrical conductivity (sigma), Seeback coefficient (S) and figure of merit (ZT) were measured at 300 K. Our aim is to investigate thermocooling behavior in respect of variation in composition of Se and Te in MoBi2(Se1-xTex)(5) thin films along with optostructural and optoelectric properties. (C) 2012 Elsevier Ltd. All rights reserved.