Abstract: Based on the daily ground-based observation data of 86 stations obtained from the Guangdong Province Meteorological Service of China, NCEP reanalysis data and ERSST datasets for the period 1979- 2017, it is analyzed the impact of sea surface temperature (SST) on spring haze in Pearl River Delta (SHD_PRD) on an interannual scale. It is pointed out that the SST of the southeast Pacific (ISSTSEP) plays a leading role in SHD_PRD. Positive (negative) ISSTSEP stimulates the eastward propagation of cold (warm) Kelvin waves through Gill forced response, causing Ekman convergence (divergence) in the Western Pacific Ocean, inducing abnormal cyclone (anticyclone) circulation. It is closely linked with positive (negative) Eurasian-Asian teleconnection pattern (EU), which results in the temperature and the precipitation enhancement (reduction) in Pearl River Delta and provides favorable local meteorological circumstances that are conducive (not conducive) to the haze occurrences. The main meteorological circumstances playing role in affecting the SHD_PRD are Precipitation, vertical velocity, and convective, next are boundary layer thickness and low-level northeast winds, and finally is moisture. ENSO in spring has a limited modulating effect on the variation of haze days in PRD region, but not the main effect. In El Nino (La Nina) spring years, the fewer (more) haze occurrence is related to increase (decrease) of the moisture, the enhancement of the vertical upward (downward) movement, and enhancement (reduction) of the precipitation.