政府购买，是国家为了满足自身履行职能的需要，而购买货物、工程或劳务的行为，是商品经济发展的产物。我国古代政府购买的历史很早，在商周时代，就有了政府购买行为的记录。春秋战国时代，商品经济有了更大的发展，各诸侯国政府经常在市场上购买粮食、军事装备、手工业原料和劳务。西汉王朝建立后，鉴于经济凋敝、国力不强的形势，前几代皇帝实行修养生息政策，个人生活也比较节俭，政府购买的规模不大。经过六十多年的努力，西汉经济发展、商品经济繁荣起来，国库也积累了巨额的财政收入，武帝即位后，发动了一系列的拓边战争和国内兴造。为了支持这些事业的进行，西汉政府在以大司农为主要负责机构的主持下，实行了规模巨大、范围极广、种类繁多的购买活动，所购买的商品上至粮食、布帛、马匹、劳务等战略性物资，下至办公用品、手工业原料和产品、薪菜、刍藁等一般性物资。西汉政府购买既依赖于农工商业的繁荣所提供的数额巨大、品种繁多的商品，也依赖于他们所上缴的巨额税收形成的巨大购买力。西汉政府购买反过来也保护了小农经济、刺激了国内生产和消费，促进了商品经济的发展，加强了国内经济联系。西汉政府购买的意义是深远的。首先，它把先秦时期形成的平准思想付诸实践并加以发展，对后世有巨大影响；其次，它使人们认识到政府购买这一经济活动能够发挥政治作用；最后，它促成了空前规模的统一的大帝国的形成，并在一定程度上延缓了王朝的覆灭。

The government purchase is behavior that the state purchases of goods, engineering or the service in order to meet the needs of their performing functions, which is product of the commodity economy development. In history, ancient Chinese government purchases are early, and can be traced back to Shang and Zhou dynasty. In Spring and Autumn era and Warring States era, commodity economy had bigger development, every state governments often bought food, military equipment, industrial raw materials and labor in the market.After the establishment of the Han dynasty, given the economic damage, national strength was not strong, the earliest several emperors had executed accomplishment interest-bearing policy, personal lives were also more frugal, the scale of government purchases was not large.After 60 years, economic and commodity economy was more prosperous; the Treasury also had accumulated massive fiscal revenue. Since Hanwu emperor had launched a series of extension edge wars and the domestic engineering. In order to support those causes of the Western Han dynasty government, DaSiNong as main responsible organization, had implemented huge scale, range and various kinds of purchasing activities. The goods which had been bought by government already up to food, cloth, horses, labor service and other strategic products, down to office supplies, handicraft materials and products, salaries dish, forage etc general supplies.Western Han dynasty government purchases not only dependent on a great quantity and great variety of goods which were provided by farmhands booming businesses, but also dependent on what they paid the huge tax form huge purchasing power. Western Han dynasty government purchases in turn had protected the small-scale peasant economy, stimulated domestic production and consumption, promoted the development of commodity economy, strengthened the domestic economic ties.The significance of western Han dynasty government purchase was profound. Firstly, it put PingZhun thoughts had formed in pre-Qin period into practice and obtained further development, had had a great impact on later generations. Secondly, it made people realize that government purchase as economic activity can play a political role. Finally, it contributed to the formation of unprecedented united empire, and to a certain extent, delaying the ruin of the dynasty.