Abstract: The people's livelihood security can be divided into bottom,basic,improving,and affluent types,according to the three dimensions of the liability,the level of protection and the difference in people's needs.The bottom type (type to meet the basic needs) is the most underpinning among the four types,and has an important index significance in the fight against poverty.It focuses on solving the most basic survival problems,becomes the foundation and prerequisites for the people's survival right,and reflects the state's responsibility for the most basic livelihoods.It is the bottom line to guarantee the most basic life,and the livelihood project and standard to ensure the basic needs of people.The livelihood items and standards are usually measured by indicators such as the average wage of employees and the minimum living security.However,the average wage index cannot reflect people's consumption expenditure,and the minimum living security line cannot be used as a suitable standard to demonstrate the basic living needs.In fact,the bottom type is related to the sum of the prices of the eight categories of consumer goods and services of urban and rural residents.By analyzing the data published around the country in recent years under the extended linear expenditure model,the researchers find that bottom type of livelihood expenses takes about 60% of the total basic demand of the eight categories of consumer goods and service prices for the urban residents.Therefore,the bottom type of people's livelihood construction should be reinforced in the national governance system and the modernization frame of governance capabilities,by continuously optimizing its expenditure structure,expanding the underpinning livelihood project types and incorporating sudden unknown diseases into the project.It will effectively enhance the openness and inclusiveness of bottom type of livelihood projects,and ensure that the “bottom” of the people's survival is effectively guaranteed.

Key words: the bottom type of people's livelihood, guaranteed livelihood, national governance