With　the　advancement　of　material　science　and　manufacturing　technology,　water　hydraulic　technology　using　freshwater　or　seawater　as　the　working　medium　has　developed　vigorously.　As　the　power　core　of　water　hydraulic　system,　the　research　direction　of　water　hydraulic　pump　tends　to　be　miniaturization,　high　power　density,　high　pressure,　intellectualization,　electro-hydraulic　integration,　which　is　widely　used　in　construction　machinery,　food　and　medicine,　fire　safety,　ocean　engineering.　Combined　with　application　requirement,　the　micro-small　water　hydraulic　bidirectional　pump　with　different　structures　in　domestic　and　abroad　are　presented,　and　the　performance　characteristics　of　different　types　of　micro-small　water　hydraulic　bidirectional　pump　are　analyzed　with　the　main　application　occasion　listed.　Compared　with　the　research　status　at　domestic　and　abroad,　it　is　found　that　the　domestic　micro-small　water　hydraulic　bidirectional　pump　has　the　problems　of　larger　volume,　lower　working　pressure　and　lower　product　maturity.　The　key　problems　that　friction　and　wear　of　bidirectional　water　lubricating　material,　sealing,　production　cost,　lack　of　structure　and　technological　innovation　in　micro-small　water　hydraulic　bidirectional　pumps　need　to　be　solved　urgently.　The　potential　main　application　prospects　of　micro-small　water　hydraulic　bidirectional　pumps　are　proposed.　This　article　provides　a　reference　for　the　development　of　micro　water　hydraulic　pump　technology.　©　2023　Chinese　Mechanical　Engineering　Society.　All　rights　reserved.