中文摘要：

按照马克思关于“社会必要劳动时间I”和“社会必要劳动时间Ⅱ”的分析思路，可从时空维度提出“社会必要劳动时间Ⅲ”和“社会必要劳动时间0”。从空间上说，“社会必要劳动时间Ⅲ”是世界必要劳动时间，“社会必要劳动时间0”是产品内分工中生产各种投入品（含中间产品）所耗费的社会必要劳动时间；从时间上说，“社会必要劳动时间Ⅲ”是社会总时间（包括总劳动时间和总休闲时间）中必须用于劳动的时间，“社会必要劳动时间0”是企业生产某种产品所必须付出的劳动时间。这四种含义的社会必要劳动时间在不同的系统层次上统一于“社会必要劳动时间”这一概念之中。

英文摘要：

According to Marx＇s analysis path about ＂social necessary labor time I＂ and ＂social necessary labor time Ⅱ＂, the paper proposes the concepts ＂social necessary labor time Ⅲ＂ and ＂social necessary labor time 0＂ from the spatial dimension and temporal dimension. From the spatial dimension, ＂social necessary labor time Ⅲ＇ is the world necessary labor time, ＂ social necessary labor time 0＂ is the social necessary labor time which must be paid for producing various inputs（include intermediate products） in intra-production division. From the temporal dimension, ＂social necessary labor time Ⅲ＂ is the time which must be used to work in the total social time （including total work time and total leisure time）, ＂social necessary labor time 0＂ is the labor time which must be paid for the production of a product in company. The four meanings of social necessary labor time can be unified in ＂social necessary labor time＂ in different levels of system.