The impact study of shrimp farming on mangrove soil properties was conducted at Surat Thani. Three sites of pond soil samples

dike, slopes of the dike and bottom

were analysed and assessed for fertility status. The data were also compared to near by natural mangrove soil properties. The result revealed that the mangrove subsoil show relatively higher chemical properties than surface soils. Their texture are generally clay. The soil reaction ranges from strongly acid to slightly acid. Electric conductivity ranges from medium to high. Organic matter, available potassium and base saturation are very high throughout the profile whereas their available phosphorus is high to very high and cation exchange capacity is high. In general, These soils have high fertility status. The pond soils have the wide range of chemical analytical values and vary more than the undisturbed mangrove soils. Their texture are generally clay. The soil reaction ranges from extremely acid to slightly alkali. Electric conductivity ranges from very low to high. Organic matter content ranges from very low to very high. Available phosphorus ranges from medium to very high. Cation exchage capacity value ranges from moderately low to high whereas avilable potassium and base saturation are very high throughout the profile. These soil have fertility status ranges from medium to high. In general the fertility status of pond soils are lower than the mangrove soil. Knowledge obtained from this investigation will be useful for pond soils improvement. In addition, this information will be helpful in considering future mangrove ultilization to maximize benefit without destroying or less disturbance to the mangrove ecosystem.