The Mouse pulsar wind nebula and its vicinity is a complex region for GeV-TeV gamma-ray astronomy, dominated by intense diffuse Galactic emission background and a dense population of potential gamma-ray emitters, such as dense molecular clouds, supernova remnants, X-ray binaries and pulsars. Thanks to its large effective area and an all-sky survey observation, the Fermi Large Area Telescope has collected a high-statistics sample of gamma rays in the GeV energy range from this region, located in projection ~1 deg from the Galactic Center.

In this study, we review the Fermi LAT observations of this region and discuss their possible relation to the TeV extended source HESS J1745-303. We discuss the interpretation of the GeV/TeV observations in terms of Very High Energy contributions, such as supernova remnant-molecular cloud interactions and/or high-spin-down flux pulsars.