Preparation　of　high-quality　functional　films　with　nanoscale　thickness　and　tunable　layers　is　highly　preferable　and　indispensable　for　optoelectronic　applications,　and　has　drawn　enormous　attention　from　research　communities.　Constructing　dense　self-assembled　monolayer　films　is　an　ideal　route　to　realize　highly　ordered　functional　films　of　optoelectronic　devices.　Moreover,　the　self-assembly　technique　can　be　used　to　construct　elaborated　micro/nanoarchitecture　for　multifunctional　and　integrated　devices　by　further　incorporating　patterning　methods.　A　review　bridging　the　controllable-assembled-monolayer　technique　and　functional　optoelectronic　devices　is　highly　desirable,　which　would　boost　the　device＇s　performance　and　even　enable　emerging　applications　like　ultrahigh-resolution　devices.　Here　we　overview　the　primary　mechanism,　material　systems,　transfer　methods,　and　device　applications　of　the　controllable-assembled-monolayers.　We　highlight　the　high-quality　quasi-lattice　monolayer　films　and　corresponding　potential　optoelectronic　applications.　A　systematic　review　of　the　controllable-assembled-monolayer　technique　will　help　further　our　understanding　of　its　potential　in　constructing　functional　films　and　optoelectronic　devices.　Systematic　review　of　the　application　of　controllable　assembled　LB　films　in　combination　with　optoelectronic　applications.