| . Along with the full liberalization of financial markets, commercial Banks in China mainly credit models to give priority to with mortgage. Real estate mortgage occupy a very important part of the value assessment, as a key link in the process of financial institutions to mortgage. Assessment of the industry in China started late, evaluation theory and practice is still in the exploratory stage, real estate appraisal is still in the phase of youth, let alone a real estate mortgage appraisal industry. Although gradually along with the socialist market economy and the continuous development of the real estate market, real estate appraisal industry is growing rapidly, real estate mortgages accounted for the real estate appraisal institutions for the purpose of more than ninety percent of the business, has become the main body of real estate appraisal, the relevant assessment criteria releasing, the related research and practice have achieved fruitful results. But the study of real estate mortgage value assessment theory, at present is still in the exploratory stage, the main is to draw lessons from other countries and regions of valuation methods. In recent years, many domestic scholars introduced a large number of real estate appraisal theory, but we can’t completely copy, should study some estimation theory system suitable for China’s national conditions, further standardize collateral valuations.Developed countries in Europe and the income approach is preferred, integral evaluation method, and easily accepted by both parties, occupies an important position in the real estate appraisal method. But in our country because of the limit of the subjectivity of income method and evaluation technique makes assessment agencies and assessment personnel rarely uses the income approach, even if the income method, the result is also questioned by the relevant departments and social people and was not accepted, that, in turn, affect the income method application in the assessment, makes the standard system of mortgage appraisal based on income approach has not been set up, and there is no clear difference from general valuation mortgage valuation techniques, and in real life there are a large number of real estate mortgage value assessment activities, the net income in the process of how to grasp the use of the income method and discount rate these two parameters has become the important subject to be solved. To this end, this paper studied the income method, around the subject, first of all, from the real estate mortgage value assessment related theory, basic principles, value types and evaluation methods of real estate mortgage value evaluation to discuss related issues. Then, by analyzing the case of international building real estate mortgage value evaluation, the assessment of the difficulties encountered in the practice are formidable, although some shortage, but the research is of great significance. |