The study establishes a reasonable, effective, feasible and credible assessment system which can be used on single exhibit in science museum. Multi objective and comprehensive evaluation is used to build the indexes of the assessment system, and then effect function comprehensive evaluation is used to confirm the computing method of each index and their weight in the system. Index, their utility function and weight comprise the whole assessment system. An empirical study is carried out based on this assessment system. The study only focuses on the result of exhibit information communication instead of the content, form, design and management. There are three first-level indexes in the assessment system built in the study: exhibit attraction, information communication effect, and audience satisfaction. There are secondary indexes under the first-level indicators. The last level index is tertiary, and all last level indicators are calculable using their utility functions. The assessment system is easy to understand and is highly feasible. The result of the assessment is simple and comparable. Apart from being used for a single exhibit, the assessment system can be applied to an exhibition which has a single theme.