To review the literature could always help us to find the limitation of past studies. This paper offers a literature review concerned with audit opinion from foreign studies to Chinese studies. Audit opinion directly reflects whether the financial statement is true and fair or not, which is the reason why audit is necessary and important.These archives could be divided into two parts, whose elements could influence the quality of audit opinion and how audit opinion impacts on companies and market. The stakeholders value audit opinion and they have different demands of audit opinion to meet their demand. For example, tax department needs the information of revenue and profit to collect tax, creditors need to know the exact number of assets to guarantee their loans, and investors prefer to learn the profitability of companies from financial statements. The article provides a holistic view of audit opinion to give other researchers an implication on which part of audit opinion needs to be studied further.

The big data era is coming, which influences the life of human beings in every aspect, such as working, studying, shopping and so on. The data could be uploaded and recorded by the digital devices like smart-phone and pad. The volume of data could provide useful information to help learn the habit of human beings and improve the efficiency of work. The domain of asset appraisal could make full use of big data to collect and sort information involving the appraised asset and market. On the one hand, market method of asset appraisal needs a plenty of information of reference substance and industry development. On the other hand, big data with the trait of volume and velocity could be utilized to collect information. The paper reveals that taking advantage of big data application in asset appraisal using market method is an evolutionary process in which the gradual understanding of the potential of big data plays a crucial role.

Big data could be utilized in work and life. Asset appraisal could also make full use of big data to improve the efficiency and effectiveness of appraisal. The paper is going to study the application of big data in different fields to learn how big data works in practices and what the effect is after utilizing the new tool. Then, the paper is going to apply big data in appraisal in specific work environment. By collecting information, researching literature and practicing with appraisers, this paper finds some means to improve market method by making full use of big data.The article researched further by applying the method in different projects of asset appraisal. Real estate, intangible asset, corporate valuation and machines could be valued by the market method improved by big data. There are different details for appraisers to be careful in practical work. Some companies have already put the technology into practice and achieved great benefit, which makes the application of big data meaningful.