Shang Jun Shu (Book of Lord Shang) is the collection of the works of the Legalist School represented by Shang Yang in the Warring States Period (475-221BC). Shang Yang (c. 390-338BC) was very interested in law when he young. In 361BC, he started the reform in the Qin State, which was called Shang Yang Reform in the history.

Shang Jun Shu recorded the theory and the specific measures of the reform of Shang Yang. In this book, Shang Yang thought the primary task was to find a way for survival at that time, but the survival depended on the enhancement of the national power.

As to the specific measures, Shang Yang intended to:

1. Enhance the regality, stipulate the jural system with strict reward and punishment;

2. Reward the military exploit, promote the furrow, and abolish the hereditary privilege of the nobles;

3. Govern the country by law, with more emphasis on law, credit and power and influence;

4. Govern with severe punishment. This idea undertaken by the First Emperor of Qin and his Prime Minister Li Si accelerated the collapse of the Qin Dynasty (221-206BC).