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In order to explore the changes in visibility in East China, using visibility data from 1973 to 2020, meteorological elements and pollutant concentration data from 2014 to 2019, the temporal and spatial variation characteristics and influencing factors of visibility are analyzed by using trend analysis, empirical orthogonal function (EOF) decomposition, and correlation analysis. The results show that from 1973 to 2020, the visibility shows a significant (p<0.01) decreasing trend, and the trend rate of change is -1.315 km/10a. There are differences between seasons. The decreasing rates of visibility in summer and autumn are 1.681 km/10a and 1.443 km/10a, respectively. The decrease rates in winter and spring are 1.092 km/10a and 1.091 km/10a, respectively. The visibility shows a significant (p<0.01) decreasing trend from 1973 to 2012, and the change tendency rate is -1.204 km/10a. The visibility shows an insignificant (p>0.05) increasing trend during 2013-2020, and the change tendency rate is 2.229 km/10a. Visibility has improved significantly in the past eight years (2013-2020). Visibility is better in the south and north of East China but poorer in the middle. The first mode of EOF decomposition shows that the overall change trend of visibility in East China is consistent. The second mode has obvious regional differences. Visibility is significantly negatively correlated with relative humidity, PM_2.5, PM₁₀, SO₂, and NO₂, and positively correlated with O₃ mass concentration. Relative humidity is the most important factor affecting visibility reduction, followed by PM_2.5 mass concentration. The relationship between temperature and pressure, and visibility is strong uncertainty.