Acid sulfate soils and salt-affected soils are widely distributed in the Mekong Delta of Viet Nam. As well as the improvement of chemical properties, it is es-sential to minimize soil structural degradation. However, relatively little research has been conducted on behaviors of aggregates in the Mekong Delta. In the present study, saline and sodic soil (SS), alluvial soil (AS), and acid sul-fate soil (ASS) were collected from the Mekong Delta. First, aggregate stability tests were conducted on them. Base on the aggregate stability test, dry clods of 2–5 mm in size under fast wetting process were used to evaluate aggregate stability of the soils after incubation with soil amendments. Chicken manure was used as a compost and eggshell-CaCO3 was an alternative for lime. Soil and amendments were mixed and incubated in a glass bottle for 45 days at a constant temperature of 25 ◦C. During the in-cubation, CO2 concentration in the headspace of the glass bottle was periodically measured. After incubation, soil pH and aggregate stability were evaluated. Mean weight diameter (MWD) was used to evaluate aggregate stabil-ity. Eggshell application increased the pH of all three soils. Compost raised the pH of SS and AS but it was less effect-tive at raising pH of ASS. The combination of compost and eggshell was the most effective at increasing soil pH. Rapid increases in CO2 emission rate after eggshell application suggested that the CaCO3 rapidly reacted with the H+ in the soils. Correlations between soil pH and CO2 emission suggested that microbial activity increased with increasing in soil pH. Eggshell application alone destabilized soil ag-gregates, whereas the compost and the compost-eggshell combination improved aggregate stability.