The aim of the article is to do some study concerned in the main part of evaluating an unlisted company in merging, namely estimating the price of an objective enterprisean unlisted company. The value of an unlisted company in merging should include not only the value of the enterprise as a whole before being merged but also the benefit (excessive value) caused by the effect of coordination and other factors in the process of merger. So the value of an unlisted company can be calculated as the value of the objective enterprise before being merged plus the excessive value.