Correlation analysis and factor analysis are used to study the relationship between the flowering of autumn osmanthus and the meteorological factors four weeks before flowering， based on the osmanthus phenology data and the meteorological data from 2004 to 2017 in Chengdu. The results show: (1) There is a negative correlation between the flowering stage and the average minimum temperature and precipitation in one week before flowering. The higher the minimum temperature in the week before flowering, the more abundant the precipitation, and the earlier the flowering is. (2) The main components of temperature and light and rainfall are extracted by factor analysis. The main components of temperature and light are most closely related to the flowering period of autumn osmanthus, and temperature played a leading role in the flowering of autumn osmanthus. (3) A score model for the comprehensive evaluation of flowering period is established by using the variance contribution rate of the first principal component and the second principal component. The period of 4 weeks before flowering (from late July to midAugust) is an important period for flowering, and also for the completion of flower bud differentiation. The comprehensive application of correlation analysis and factor analysis can better reflect the relationship between meteorological factors and the flowering of autumn osmanthus, reveal the influence of meteorological factors on the flowering, and provide scientific and technological supports for the meteorological service for autumn osmanthus flowering in Chengdu.