Abstract: Municipal solid waste incineration is the dominant waste treatment method in China, generating significant amounts of fly ash that are rich in heavy metals with varying types and concentrations. Traditional methods like ICP-MS are time-consuming and unsuitable for real-time monitoring, necessitating the development of an online in-situ detection technique. Therefore, there is a critical need for the development of rapid, online detection techniques for heavy metals in municipal solid waste incineration fly ash. Laser Induced Breakdown Spectroscopy (LIBS) has emerged as a promising analytical method for the real-time monitoring of heavy metals in municipal solid waste incineration(MSWI) fly ash. This technique has been successfully applied across various fields, including gas analysis, soil characterization, water quality assessment, and metallurgical processes, but matrix effects from complex sample compositions significantly hinder its quantitative accuracy. This study applied LIBS for the quantitative analy