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Since 2000, drought has occurred frequently in Southwest China, which has seriously affected social production and ecological environment. Therefore, studying the temporal evolution characteristics of meteorological drought and its impact on vegetation growth can provide theoretical basis for scientific management of regional water resources and ecological control. Based on the monthly precipitation and temperature data of Southwest China from 2000 to 2018, the standardized precipitation evapotranspiration index of different time scales was calculated. The linear trend method and Mann-Kendall (M-K) test were used to analyze the temporal variation characteristics of meteorological drought in Southwest China. The effectiveness and difference of solarinduced chlorophyll fluorescence (SIF), normalized differential vegetation index (NDVI) and enhanced vegetation index (EVI) in vegetation stress monitoring were evaluated. Furthermore, the response of vegetation to drought was also explored. The results showed that SPEI values showed a weak increasing trend in all time scales from 2000 to 2018. From 2000 to 2013, SPEI-12 showed a downward trend (the trend rate was -005/(10a), R2=0.295), and from 2014 to 2018, SPEI-12 time series showed an increasing trend (the trend rate was 004/(10a), R2=0.094), indicating that the drought trend in Southwest China was alleviated in recent years under the background of climate change. The turning point of SPEI-12 time series occurred in 2016 and 2017 respectively. Compared with NDVI and EVI, SIF showed obvious negative anomalies for both longterm and shortterm drought events during vegetation growing season, and it can quickly obtain the information of vegetation photosynthesis under water stress. The correlation between SIF of forest, farmland and grassland and meteorological drought index at different time scales was higher than NDVI and EVI, which meant that the sensitivity of SIF of forest, farmland and grassland vegetation ecosystem to drought monitoring was better than that of traditional vegetation greenness index. The correlation between SIF of grassland and SPEI-1 was higher (R=0.859, P<0.01), which indicated the grassland photosynthesis was more sensitive to shortterm water stress. The research results can provide scientific basis for comprehensive drought coping, water resources management and ecological control in Southwest China. 