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Savannas cover 60% of the land in southern Africa, with fires and herbivory playing a key role in their ecology. The Limpopo National Park (LNP) is a 10.000 km2 conservation area in southern Mozambique and key to protect savannas in the region. Fire is an important factor, but little is known about its interactions with the ecosystem. In this study we investigated the effects of fire frequency (FF) on vegetation and fauna of the LNP. To understand the FF, we used the MODIS burned area and active fire products for 10 years (2003-2013). A total of 6 ha was sampled to assess biodiversity across three landscapes (Nwambia Sandveld-NS, Lebombo North-LN and Shrub Mopane on Calcrete-C) and two FF levels (low - twice or less; and high - 3 times or more during 10 years). FF was higher in NS and LN landscapes, where 40% of the pixels burned in 10 years. The landscape type determined grass composition and biomass. The latter was higher in the sandy NS and under high FF. The three landscapes belonged to 3 different tree communities, but FF produced varied compositional responses in NS and LN. Low FF resulted in a higher plant abundance and phytomass of small trees (<2m) in LN and C. The composition of small mammals in the three landscapes was similar: Aethomys chrysophilus, Mastomys natalensis and Elephantulus brachyrhyncus, but the relative abundance was higher in NS (41%). Synthesis: This study revealed that grass and woody structure and composition in LNP are determined by the landscape, but FF imposes some important variations. These results indicated that, an increase in FF may result in a varied structure of the savannas, but at the current levels FF is not dramatically affecting the existence of this ecosystem in the LNP.