Phytosociological studies were made for the thirteen stands of Chakaria Sundarbans, Chittagong. Soil factors such as profile, texture, ground water table, pH and salinity were studied. Depending on the characteristic species four phytosociological zones were recognised which were related with the various ecological factors. Maximum soil salinity ranging from 10 mmhos to 33 mmhos were recorded in the Avicennia- Sonneratia- Aegialitia zone. In this zone water table ranges from few cm to 30 cm (11.8 in). Soil profile differentiation is not well marked. Soil is more silty than other zones. Heritiera – Brugtiiera zone occur in the soil with least salinity conductivity ranging from 7.5 mmhos to 2.5 mmhos. Water table ranges from 100 cm (34.3 in) to 150 cm (59.1 in). Soil profile is differentiated into various horizons in this zone. In the field condition surface soil shows pH range from 6.2 to 7.5. The air dried soil shows a fall of pH value to 3.4 in some stands.