China has the largest population in the world, about 1.2 billion people. Before liberation there were only 400 million people. But shortly after liberation in 1949, China began to have a population explosion. The standard of living has been rising and people have obtained better and better housing, while medical care and job security have been improved. As a result, the average life expectancy of our nation is going up rapidly, as well as the birth rate. With a population explosion, a series of other problems will emerge. There will be a lack of land, food supply, water, fuel and so on in our country. The consequence of the problems will threaten human life. Therefore, in order to stop these terrible consequences, we have used family planning to control the birth rate. At the same time, we should take other effective steps to make sure people everywhere continue to limit their families through birth control.