Understanding a situation requires integrating many pieces of information which can be obtained by a group of data collectors from multiple data sources. Uncertainty is involved in situation assessment. How to integrate multi-source multi-member uncertain information to derive situation awareness is an important issue in supporting decision making for crisis problems. The study focuses on how uncertain situation information is presented, integrated and finally how situation awareness information is derived. A multi-sources team information integration approach is developed in the study to support a team's assessment for a situation in an uncertain environment. A numerical example is then shown for illustrating the proposed approach.