The main objectives of this study is to (i) survey some chemical properties of alluvial soil in rice-growing areas dykes
(ii) to determine grain yield of rice in dikes at the province of An Giang. This study was done in the winter-spring season 2011. Nutrient content of dyked rice soils in two surveyed areas was quite variable among surveyed locations (6-15 percent). Both areas had content of N and organic carbon from low to moderate level, but the N and available P content are high. Grain yield at the alluvial soil in the land with dikes still remains at high levels, from 7.8 to 8.2 ton/ha on average, but there were no differences between the two locations. Although rice soil in Long Hoa is the dike with periodically flood discharge, the properties such as pH, organic matter, total nitrogen and organic nitrogen of soil are higher than that of rice soil in Kien Thanh (high-dyke area). However, this finding cannot conclude that the effects of flood discharge because their locations are far apart and the initial soil properties are not defined by its uniformity. It need to conduct other experiments on the effects of flood discharge in accordance with scientific standards on the same location in order to attain more objective conclusions.