Fullerene ethylenediamine dinitramide was synthesized via ion exchange reaction of fullerene ethylenediamine nitrate and ammonium dinitramide (ADN). The structure of fullerene ethylenediamine dinitramide was characterized by UV-Vis, FT-IR, elemental analysis and XPS. Its thermal decomposition characteristics were investigated by thermogravimetric-differential thermogravimetry (TG-DTG), differential scanning calorimetry (DSC) and differential thermal analysis (DTA). Results show that the molecular formula of fullerene ethylenediamine dinitramide is H₁₂C₆₀(HNCH₂CH₂NH₂·HN(NO₂)₂)₁₂. DSC curve shows that fullerene ethylenediamine dinitramide starts to decompose at 150 ℃ with thermal decomposition peak temperature 203 ℃ and decomposition enthalpy 1037.7 J·g^-1. TG study indicats the total mass loss in the temperature range 100-800 ℃ is 49.68% with intense decomposing of N(NO₂)₂^- and part of the branched chain decomposing.