Abstract: In today's diverse and open society, religious traditions and moral perfectionism compete against each othera phenomenon which demonstrates a normal state and a lasting character of modern society. To provide everyone a unified and objective and perfect morality and a way of good life based on a certain theory is no longer acceptable to modern people' hearts; it would ruin people's moral life and human nature. Moral bottom line rule regulates every society member's behaviors by stipulating the least basic moral obligations, thereby building afundamental defense system for human to survive, at the same time ensuring people to pursue their life ideals and moral goodness freely and safely. Moral education needs to guide youths to make equal and open moral dialogues with other people in this diverse society, and to pursue wider moral consensus and ultimate good freely while holding on to moral bottom line.

Key words: Moral Education, Moral Bottom Line, Perfect Morality