Fischer　esterification　referred　to　the　reaction　of　carboxylic　acids　and　alcohols,　which　was　generally　catalyzed　by　Brönsted　or　Lewis　acidic　catalysts.　Basic　ionic　liquids　with　the　nucleophilic　anion　were　generally　considered　incapable　of　catalyzing　this　reaction　due　to　sufficiency　of　electrons　or　the　lack　of　ionizable　protons.　Herein,　bisimidazolium　tungstates　were　found　be　able　to　catalyze　Fischer　esterification　of　ethylene　glycol　(EG)　and　benzoic　acid　relying　on　the　nucleophilic　WO42−　anion.　The　mechanism　studies　indicated　that　C6H5COO−　and　H−WO42−　anionic　intermediate　was　formed　between　benzoic　acid　and　WO42−　via　hydrogen-bond　interaction　under　the　influence　of　hydroxyl　of　EG.　This　intermediate　could　further　release　H　atom　to　accelerate　the　reaction　speed　of　Fischer　esterification,　which　was　similar　catalytic　process　to　that　of　Brönsted　acidic　catalysts.　Furthermore,　other　nucleophilic　anions　(CO32−,　OH−,　OAc−,　C6H5COO−)　had　little　catalytic　capacity　in　the　reaction.　This　suggested　that　the　strength　of　anionic　nucleophilic　ability　played　an　important　role　in　the　esterification　reaction.　©　2023　Wiley-VCH　GmbH.