Sensors with high-sensitivity for resistive methanol gas detection are highly desirable. Herein, we report newly designed ultrathin anionic metal-organic framework (MOF) nanosheets (NSs), with an average thickness of 10 nm and an electrical conductivity of 3.77 × 10-4 S cm-1. The ultrathin MOF NSs can be used as the active material in an electronic methanol gas sensor, which exhibits high sensitivity toward methanol gas at room temperature, i.e., high Rair/Rgas (363.2 at 100 ppm), fast gas response/recovery speed (6 s/2 s at 20 ppm), long-term stability, and superior cross-selectivity against other interfering gases.