An　asymmetric　InAlGaN/GaN　superlattice　barrier　structure　without　the　first　quantum　barrier　layer　(FQB)　is　designed,　and　its　effect　on　the　optoelectronic　performance　of　GaN-based　green　laser　diode　(LD)　has　been　investigated　based　on　simulation　experiment　and　analytical　results.　It　is　found　that,　compared　with　conventional　GaN　barrier　LD,　device　performance　is　significantly　improved　by　using　FQB-free　asymmetric　InAlGaN/GaN　superlattice　barrier　structure,　including　low　threshold　current,　high　output　power,　and　high　photoelectric　conversion　efficiency.　The　threshold　current　of　LD　with　novel　structure　is　16.19　mA,　which　is　22.46%　less　than　GaN　barrier　LD.　Meanwhile,　the　output　power　is　110.69　mW　at　an　injection　current　of　120　mA,　which　is　16.20%　higher　compared　to　conventional　LD,　and　the　wall-plug　efficiency　has　an　enhancement　of　9.5%,　reaching　20.27%.　FQB-free　asymmetric　InAlGaN/GaN　superlattice　barrier　layer　can　reduce　optical　loss,　suppress　the　polarization　effect,　and　improve　the　carrier　injection　efficiency,　which　is　beneficial　to　improve　output　power　and　photoelectric　conversion　efficiency.　The　novel　epitaxial　structure　provides　theoretical　guidance　and　data　support　for　improving　the　optoelectronic　performance　of　GaN-based　green　LD.　©　2024　The　Electrochemical　Society　(“ECS”).　Published　on　behalf　of　ECS　by　IOP　Publishing　Limited.