Abstract: Double layered perovskite manganites La_2-2xSr_1+2xMn₂O₇ （0.2≤x≤0.6） were synthesized by sol-gel method and conventional solid state reaction method. X-ray powder diffraction was tested to characterize the crystal of the samples. The analyses indicate that the crystals are single-phase with I4/mmm tetragonal lattice symmetry. As the strontium concentration increases, the parameter a prac-tically does not change, whereas the parameter c decreases. Extend X-ray absorption fine structure （EXAFS） measurements at the Mn K-edge as a function of doping level x were performed on La_2-2xSr_1+2xMn₂O₇. All samples have a Jahn-Teller （J-T） distortion, further more, the J-T distor- tion magnitude Δ_JT gets the biggest value at x=0.33. Simultaneously the Debye-Waller factor σ² for the Mn-O（1） and Mn-O（2） atom pairs vs x are similar to Δ_JT. These results suggest that the mag- netism-electricity of layered perovskite manganites La_2-2xSr_1+2xMn₂O₇ is closely related with the Δ_JT.