Under UV-laser excitation, the Porites coral from Longwan bay waters, Hainan Island, could emit yellow-green fluorescence. After fitting the data of the fluorescent intensity (FI) of the coral with the rainfall (RF) in nearshore area of Qionghai, a good relationship between FI and RF was found with a linear formula of RF= 889 - 4. 54 FI and a correlation coefficient of 0.78. Based on this formula, the rainfall sequence from 1982 to 1997 has been reconstructed. The peak annual rainfall is usually related to global El’nino events. By fitting the data of the fluorescent intensity and the runoff (RO), a quadric formula was obtained as RO = - 0.0279FI2 - 18.59 FI- 950.9 with a correlation coefficient of 0.74. The reconstructed runoff sequence from 1982 to 1997 coincided with the rainfall occurrence . The results indicate that flood and drought incidents in coastal areas of the south China are affected by global change to a great extent. Under UV-laser excitation, the Porites coral from Longwan bay waters, Hainan Island, could emit yellow-green fluorescence. After fitting the data of the cove with the rainfall (RF) in nearshore area of ​​Qionghai, a good relationship between FI and RF was found with a linear formula of RF = 889 - 4. 54 FI and a correlation coefficient of 0.78. Based on this formula, the rainfall sequence from 1982 to 1997 has been reconstructed. The peak annual rainfall is usually related to global El’nino events. By fitting the data of the fluorescent intensity and the runoff (RO), a quadric formula was obtained as RO = - 0.0279FI2 - 18.59 FI- 950.9 with a correlation coefficient of 0.74. The reconstructed runoff sequence from 1982 to 1997 coincided with the rainfall occurrence. The results indicating that flood and drought incidents in coastal areas of the south China are affected by global change to a great extent.