Hypersaline lakes are extreme environments with limited microbial diversity due to the combined effects of multiple environmental factors, including increased salt concentrations, temperature, pH and low nutrient and oxygen availability. Great Salt Lake (GSL), Utah is used as an analogous site for astrobiology field research, it’s shifting salinity gradients and high UV doses provide models for exploring the limits of life[1]. Resident microbes survive desiccation and become entrapped in minerals as they form. Athalassohaline environments have an ionic composition very different to seawater and are dominated by anions other than chloride (e.g. sulphates) and cations such as magnesium and calcium[2]. Cellular life in these environments is dominated by prokaryotes (Bacteria and Archaea), with few Eukaryotes[3]. The use of culture-independent techniques typically demonstrates a higher diversity of uncultivated microbial species from hypersaline environments[4]. Most studies previously have focused on the diversity of thalassohaline environments, while athalassohaline environments remain relatively untouched. Lake Eyre is an athalassohaline hypersaline environment, located 700 km north of Adelaide, South Australia and spans over 9000 km2. It’s major catchments stem from the Great Artesian Basin in it’s northeast corner, and summer monsoon waters from Queensland[5]. Roughly 1/3 of the lake, predominantly the south-end, is salt crusts, the northern sections tend to be more of a slush zone with a thin layer of salt crusts above mud that doesn’t dry[6]. There have been no studies conducted on the microbiome of Lake Eyre. The aim of this study was to assess, via metagenomic analysis, the taxonomic diversity and functional capacity of hypersaline environments analogous to Martian environments. With high levels of annual UV dosage and abundance of salt crystals, Lake Eyre shares similar characteristics to GSL. Euryarchaeota was the most abundant phylum with ~96% distribution, Proteobacteria were the most abundant bacterial phylum at 1.49% (Alphaproteobacteria 1.17%; Deltaproteobacteria 0.18%; Gammaproteobacteria 0.15%). Functional analysis shows resident microbes are capable of carbon fixation (~2.1% abundance), sulfur and nitrogen metabolism (~0.5% and 0.98% abundance respectfully). Various transport and biosynthesis pathways for organic solutes were found in abundance; further providing osmotic protection at increased salinities. The results help to unravel the complexity of poorly the characterised taxonomic and functional abundance of Athalassohaline environments, in turn, discovering possible novel organisms and survival strategies.