The concept of confidence distribution of population characteristic is presented in this paper.Based on the confidence distribution

a new theory of confidence tests is established

which includes three kinds of tests:strong test

weak test and weak strong test.The confidence tests are based on The Law of Small Probability

while the significance hypothesis tests are based on The Law of Large Probability.Compared with hypothesis tests

the confidence tests can inspect and control the quality of products with higher precision

and overcome the disadvantage that to accept a null hypothesis may simply mean that it is not rejected by significance hypothesis tests.In addition

the application of the confidence tests can greatly improve the test precision and bring more convenience in engineering.