From the experience of agricultural development in various countries in the world, if traditional agriculture wants to transition to modern agriculture, it is necessary to change the agricultural production goal from maximizing the output of self-sufficiency consumption to maximizing the profit of commodity production. The necessary conditions to complete this transformation are the decline of the proportion of agricultural labor force and the relief of the pressure of agricultural population. China is a big agricultural country, and it is bound to face many difficulties in completing this transformation. However, the biggest obstacle in this transformation process is the existence of a huge agricultural population. There are many reasons for this situation: first, ideological reasons. China experienced a long feudal society, and people did not get rid of the influence of feudal natural economy. Many children are blessed, and the objective requirements of family values and manual labor for human resources have stimulated the rapid growth of population in China, making the contradiction between man and land more prominent. In recent years, due to the implementation of the family planning policy in China, the rapid population growth has been curbed. However, the huge inertia of population growth has reduced the birth rate of China population, but the absolute number of new population is still very large. The second is institutional reasons. During the nearly 30 years from the founding of People's Republic of China (PRC) to the Third Plenary Session of the Eleventh Central Committee in 1978, China has been implementing the household registration system of separating urban and rural areas, strictly controlling the inflow of rural population into cities, and a large number of laborers have settled in rural areas. After the Third Plenary Session of the Eleventh Central Committee, with the implementation of the household contract responsibility system, this "stable" situation was broken, and the long-standing hidden unemployment in rural areas gradually emerged. The third is resource reasons. China is a country with scarce cultivated land resources. 1994, China's cultivated land area was14.24 million mu, and the rural population was 855.49 million. The average cultivated land occupied by each agricultural population is only 1.66 mu, which is less than 1/27 of the average cultivated land of rural residents in the United States and 3.88 of that of agricultural population in India. The number of agricultural laborers per 100 hectares of cultivated land in the United States is 1.89, while the number of agricultural laborers per 100 hectares of cultivated land in China is as high as 350, and the contradiction between people and land is very prominent. However, the upsurge of development zone fever, real estate fever and the expansion of urban and rural housing sites since the 1990 s has further aggravated this contradiction. Many fertile fields have been turned into development zones, but they have been "opened without development" or "closed without development" for a long time, resulting in serious land waste. The fourth is the industrial structure. For a long time, China's agricultural industrial structure is not reasonable, which has a profound historical origin. First of all, from the mode of industrialization, in some developed countries and regions, the process of industrialization is light industry-basic industry-heavy industry, with special emphasis on the development of the tertiary industry. Therefore, it can effectively absorb the surplus agricultural labor force, so that a large amount of rural land can be cultivated by a few agricultural producers, which is convenient for the formation of scale benefits and mechanized farming. The development of industry also provides agricultural machinery, fertilizers and pesticides for agriculture. This industrialization mode of absorbing rural population and feeding back agriculture has made these countries and regions move towards a virtuous circle of coordinated development of industry and agriculture. However, in the process of industrialization, China has taken a road of giving priority to the development of heavy industry. On the one hand, this industrialization model was influenced by the experience of the Soviet Union, on the other hand, it was also related to the international political, economic and military pattern that China was facing at that time. After the founding of New China, the tense international situation made China leaders realize that rapid economic development and national strength are the most important things for the survival of the country and the nation. The development of heavy industry will not be limited by narrow market and insufficient demand. This unconventional catch-up development model, which aims at giving priority to the development of heavy industry, can not only effectively absorb rural surplus labor, but also crowd out too much agricultural surplus. Secondly, from the perspective of agricultural industrial structure itself, China's agriculture has long had a single industrial structure, mainly planting. The proportion of forest sideline and fishery is small, township enterprises started late, and the tertiary industry is rising, but the development is uneven. The agricultural industry in most areas is still road agricultural products. Although great changes have taken place in the coastal rural industrial structure of China in recent years, on the whole, the unreasonable agricultural industrial structure has not changed.
To sum up, in China, a big agricultural country, the process of agricultural modernization is bound to face many difficulties, such as the relatively small per capita land resources in China; The stock of agricultural population is huge; The level of urbanization is low, and there are a large number of unemployed and laid-off workers in cities; Irrational agricultural industrial structure and many other problems. Facing the opportunities and challenges brought by China's entry into WTO, if China agriculture wants to get out of the predicament and get rid of the current unfavorable situation, only the transformation from traditional agriculture to modern agriculture is the fundamental way out for the sustainable development of agriculture in China.