Abstract: In Being and Time,Heidegger holds that the space of the world must be explicated by the space of Dasein,and the space of Dasein originates from the temporality of Dasein.Temporality was considered as the sense of authentic care and a foundation of spatiality,and space and spatiality are less “original” than  time and temporality.However,Heidegger,at the same time,also regards that to say temporality lays a foundation for spatiality or to say temporality is prior to spatiality is temporarily valid only in the preparatory analysis of Dasein’s structure of temporality,afterwards,the relationship between time and space will be equalized expressly.In Time and Being,Heidegger finished this task.He called the horizon,in which the sense of being was understood,with the name “time-space”，considering that only in the disclosed state of the original time-space,can the being of things,Dasein and“Ereignis” make their appearance.

Key words: Heidegger, Dasein, space, spatiality, time, temporal