This paper analyzes the process by which con dien 公田 or state-owned ricefields of the 15th century became communal land by the 19th century, through an examination of some regulations covering the Land Distribution System during the Minh Mang 明命 period. This is the ninth report of the study on the Vietnamese traditional land distribution system. Part I, A regulation of 1803 permitted the village chiefs to mortgage cong dien in their villages for up to three years. In spite of objections by local officials, the central government defended this regulation through the Minh Mang period in order not to disturb the political status quo in the villages. Part II, The intention of the central government to make accurate land rolls had to be revoked, most probably because of the existence of strong village autonomy. In relation to this point, there are some indications of the existence of strong village autonomy during the Minh Mang period. Most of the existing traditional land rolls from 1805 to 1889 are essentially the same and they show no sign of having been updated. The total number of officially recorded ricefields in North Vietnam decreased between 1819 and 1861, despite the extensive agricultural development of the region during this period. A regulation of 1834 stipulated that even when thitherto unregistered land was discovered, its "owner" was permitted to continue to possess it as long as he paid a land tax for one year. Part III, A regulation of 1817 proclaimed that village chiefs who hid villagers from official registers were to be severely punished. The system of registering adult tax paying males was improved by a regulation of 1827. Apparently on account of these legal measures of the central government, the number of registered males and the total amount of poll tax collected increased during the Minh Mang period. 0n the other hand, the conscription of registered males was not so effectively carried out, probably due to the sabotage of village chiefs. This may indicate that the village chiefs were selective in the kind of government orders they were willing to comply with. Part IV. A regulation of 1828 concerning the appointment of village chiefs aimed to control the selection process of the political leaders of a village. This regulation, however, was essentially the recapitulation of the already existing regulation dating back to the Le 黎 dynasty. This fact strongly suggests that the regulation of 1828 was an administrative "garnish" which was difficult to implement. part V. A regulation of 1840 concerning the land distribution system renounces the privileged share of officials in the cong dien. This means that the regulation of 1840 (see Sakurai, 1977) officially recognized the right of the village to control the cong dien as communal land. In conclusion, the so-called political centralization of the Minh Mang period essentially meant administrative centralization without necessarily any accompanying concomitant social or economic centralization at the village level. It is my contention that this administrative centralization in fact strengthened village autonomy.