Abstract: The quality control method of resistance ratio of Carlson transducer has been written into the specification and has played a positive role. This paper points out the shortcomings, puts forward a new expression to resistance ratio error, analyzes the resistance ratio characteristics, compares the methods to calculate the resistance ratio error and gives a recommendations to modify the current specification. The resistance ratio accuracy of five-core or three-core or four-core Carlson transducer can be judged by use of the sum of pro and con resistance ratio, as well as the product, in which the latter is more reasonable.