[Objective] This study aimed to clarify the quantitative relationships between growth parameters of sweet corn at different growth stages and canopy spectral indices,thus providing references for rapid monitoring of growth parameters of sweet corn.[Method] Based on field experiments of Zhengtian 68 under different potassium application levels,canopy spectral reflectance was collected using CGMD302 spectrometer at jointing stage,big bell mouth stage and tasseling stage,respectively;plant height,stem diameter,and leaf area index（LAI） were measured,to investigate the relationships between various growth parameters and spectral indices.[Result] Normalized difference vegetation index（NDVI） was positively correlated with stem diameter and LAI;ratio vegetation index（RVI） was negatively correlated with stem diameter and LAI.The single-stage monitoring models established based on NDVI and RVI could retrieve effectively stem diameter and LAI of sweet corn with the prediction accuracy of higher than 0.9,root mean square error（RMSE） of less than 10%,average relative error（RE） of less than 5%.[Conclusion] This study provided a technical basis for rapid monitoring of growth parameters of sweet corn.
