Tl-2212 superconducting thin films were fabricated on LaAlO3 (00l) substrates by sol-gel method. In the process, the precursor films were annealed in various gas atmospheres. XRD and EDX testing results showed that the precursors annealed in O2 converted into pure Tl-2212 superconducting phase, and the nominally stoichiometric cation ratio of TlBaCaCu was close to 2:2:1:2. The Tl-2212 film had a layered morphology and medium-quality superconductive parameters, which included the critical temperature T c of 105.5 K, and the critical current density J c of 0.8 MA/cm2 (self-field, 77K).