Abstract: The unconfined compressive strength is a representative strength in geotechnical design. Based on 186 sets of unconfined compression test(UTC) of marine soft soils in Lianyungang area,the stress-strain curve types were classified and statistically discussed,and the factors affecting the stress-strain curve were discussed. The results showed that the stress-strain curve types can be categorized into three types. Type Ⅰ curves are softening type,with obvious peak axial stress,and the number of type Ⅰ curves accounts for 27%; Type Ⅱ curves are stable,without obvious peak,and the axial stress generally converges to a constant value only after the strain is greater than 15%. The number of Type Ⅱ curves accounts for 35%; Type Ⅲ curves are strain-hardening type. When the strain is greater than 20%,the axial stress has not yet converged,and the number of type Ⅲ curves accounts for 38%. Vibration can lead to the gradual transformation of the stress-strain curve type from type Ⅰ to type Ⅲ,and the damage strain becomes larger with the increase of vibration duration,and the value of unconfined compressive strength gradually decreases. The type of sampler also has a significant effect on the curve type. 90% of the type Ⅰ curves are obtained by thin-walled samples,and only 10% of the type Ⅰ curves are obtained by the thick-walled samples. K₀ consolidation pretreatment can restore the soil ground stress and promote the curve type to be transformed from type Ⅱ and Ⅲ to type Ⅰ. The obtained shear strength is close to the soil shear strength obtained from the in-situ test,and the more obvious the soil stress recovery effect is carried out with the increase of sampling depth.