In order to clarify the effects of alien species invasion on soil carbon (C), nitrogen (N), phosphorus (P) and their ecological stoichiometric ratios in coastal wetlands with different textures, the contents of soil C, N, P and their ecological stoichiometric characteristics, as well as influencing factors of Donghu Wetland with sandy and loamy textures in coastal areas of Fujian Province were measured and analyzed. The results showed that the contents of soil C, N and P and their stoichiometric ratios were higher in the loamy soil than that in the sandy soil under the same vegetation. The invasion of Spartina alterniflora increased the C and N contents, the ratios of carbon to phosphorus (C/P) and nitrogen to phosphorus (N/P) of the two textured soils, and decreased the soil P content and the carbon to nitrogen (C/N) ratio, with a significant increase of almost 1 times (P<0.05) in the soil N content and a decrease in the AP content of nearly 70% in sandy soils, as well as a significant increase of almost 2 times (P<0.05) in the C/P in loamy soils. The invasion of Spartina alterniflora had different effects on the content of ammonium nitrogen (NH₄⁺-N) and nitrate nitrogen (NO₃^--N) in soils of different textures. In loamy soils, Spartina alterniflora invasion decreased the NH₄⁺-N content by 50% and increased the NO₃^--N content by almost 3 times (P<0.05). However, in sandy soils, the NH₄⁺-N content increased almost 3 times after Spartina alterniflora invasion (P<0.05) and the NO₃^--N content showed a decreasing trend.The C/P and N/P of both textured soils were significantly negatively correlated with P (P<0.05), but not significantly correlated with C and N. In sandy soils, soil N content was significantly negatively correlated with bulk density, while positively correlated with water content (P<0.05). In general, although the effects of Spartina alterniflora invasion on C, N, P and their ecological stoichiometric ratios for different textures soils are different, the trends are roughly the same. The invasion of Spartina alterniflora will increase the contents of soil C and N, but reduce the P content of the soil, thus exacerbate P limitation in coastal wetland soils.