Abstract: 【Objective】 Proteomics analysis of two tropical maize inbred lines under long sunshine condition was conducted to provide theoretical basis for the molecular regulatory mechanism of maize under long sunshine condition.【Method】 Photosensitive(FT32) and photonesthesia(FQR273) tropical maize inbred lines were selected as materials,and differential proteins were screened by tandem mass tag(TMT),and their GO function annotation and KEGG signal pathway enrichment analysis were performed to construct the interaction network between differential proteins.【Result】 A total of 6082 effective proteins were identified from leaf samples of four-leaf stage of FT32 and FQR273 tropical maize inbred lines under long sunshine conditions,among which 605 were significantly differentially expressed(107 were up-regulated and 498 down-regulated). And 605 differential proteins were annotated into three categories of biological process,cell components and molecular functions,with a total of 79 items. In the classification of biological process,the main annotations were translation process,glutathione metabolism process and protein folding. In the classification of cell components,the main annotations were integral components of membrane,cytoplasm and chloroplasts. In the classification of molecular functions,the main annotations were ATP binding,metal ion binding and the structure composition of ribosome. Moreover,140 differential proteins were enriched to 13 KEGG signal pathways,which were mainly enriched in secondary metabolite biosynthesis,porphyrin and chlorophyll metabolism,and amino acid biosynthesis. Phosphate synthetase,ribosome metabolism and translation process were the key pathways of maize leaves under long sunshine conditions. A total of 196 functionally annotated proteins were classified and analyzed in depth,and were divided into four categories according to biological functions.The proteins were involved in reactive oxygen species(ROS) homeostasis(33), protein metabolism(59),related transferases(25),and other functions(79).【Conclusion】 Under long sunshine condition,ROS homeostasis,protein metabolism related proteins and related transferase activity of photosensitive FT32 maize are down-regulated compared with photonesthesia FQR273 maize. Other functional proteins are diverse and have complex functions,and play their roles in different ways. In other words,under long sunshine condition,photosensitive FT32 maize leaves mainly regulate ribosome metabolism and translation process to maintain the normal growth of maize.