In the present research technology of compositionally graded barium strontium titanate Ba Sr TiO thin films deposited on stainless steel substrates by sol-gel spin coating followed with thermal annealing at = 650°C is reported. Results of thermal behavior of the sol-gel derived powders with compositions used for fabrication of graded structure (i.e. with Sr mole fraction = 0.5, 0.4 and 0.3) are described. X-ray diffraction studies of the phase composition and crystal structure of such complex thin film configuration are given. It was found that gel powders exhibited a large total weight loss of about Δ ≈ 44-47%. Three stages of weight loss took place at temperature ranges: below ≈ 300°C, at Δ ≈ 300-500°C and between = 600°C and = 800°C. Phase analysis has shown that the dominating phase is Ba Sr TiO compound while the second phase is Ba Sr TiO or Ba Sr TiO for “up-graded” and “down-graded” structure, respectively.