The first successful fabrication of metal halide Perovskite MAPbI3 Film for NH3 gas sensing using fractal electrode structure is reported. High performance NH3 gas sensor was fabricated on ITO glass substrate by laser-patterning method. Gas sensors were fabricated using Hilbert, Peano, and Gosper curve structure electrodes, and their performance is compared to conventional interdigitated electrode. Gas sensing performance on Hilbert electrode design showed the highest response of 2.82 at 10 ppm NH3 gas, which is 145 % times higher compared to conventional interdigitated structures. Simulation study demonstrates that the electric field intensity and number of nodes of the fractal electrode are higher than those of the traditional interdigitated electrode. This study demonstrates that fractal electrode is a feasible strategy for optimizing the potential performance of MAPbI3-based Perovskite gas sensor with low-cost fabrication with no extra processing. Display omitted •Fractal electrode improves MAPbI3-based NH3 gas sensing response.•Complexity of the fractal curve results better edging effect.•High current density facilitates the electron transfer process.