Materials on the GeTe-Sb2Te3 pseudo-binary line, in particular Ge2Sb2Te5 (GST225), are considered to be the most perspective for the application in phase change memories. However, despite the successful commercial application of Ge2Sb2Te5 this material is not yet well studied. In particular, mechanism and kinetics of the phase transition, which determines operation rate of the memory devices, are not fully understood. Therefore, the aim of this work was investigation of the crystallization kinetics for Ge2Sb2Te5 thin films by the differential scanning calorimetry (DSC) and measurements of the resistivity temperature dependences. Ge2Sb2Te5 films were deposited by magnetron sputtering. According to atomic force microscopy (NT-MDT Solver Pro) the thicknesses of the films were in the range 130-170 nm. The amorphous and crystalline structures of the as-deposited films and films after annealed at the 450 °C, respectively, were checked by X-ray diffraction (XRD) performed by Rigaku Smart Lab diffractometer. Scanning electron microscope (Philips XL 40) with EDXR spectrometer revealed agreement between the compositions of the spattered target and deposited thin films. The resistivity temperature dependences of thin films were investigated on a special stand, containing heating stage HFS600E-PB4 Linkam and picoammeter Keithley 6485. Differential scanning calorimetry (DSC-50, Shimadzu) was used for the investigation of thermal properties and thermally induced transformations. Measurements carried out at different heating rates in both methods were used for the estimation and comparison of the crystallization kinetics parameters. Exponential temperature dependences for resistivities of amorphous thin films in the range from room temperature to 140 °C were observed for all cases. The activation energies of conductivities were 0.42 eV for all films. Sharp drop in resistivity for GST225 were observed in the ranges from 140 to 180 °C. DSC and XRD data showed that drops of the resistivities were caused by the phase transformation from amorphous to metastable rock salt structure. Developed methodics including application of the isoconversional model-free method of Ozawa-Flynn-Wall (OFW) for resistivity temperature dependences of thin films, and joint application of OFW, and Coates-Redfern model-fitting method were used for the estimation and comparison of the crystallization kinetics parameters obtained by different methods. It allowed to define influence of the substrate on the crystallization process. Analysis of the obtained results showed that crystallization process is accompanied by the decrease of the activation energy (from 2.88 to 2.54 eV), indicating that crystallization is a complex process consisting of two stages – nucleation and crystalline growth. Thus, crystallization kinetics and parameters for Ge2Sb2Te5 thin films were investigated by DSC and measurements of the resistivity temperature dependences, which allowed to analyze influence of the substrate on the crystallization process.