Temperature is one of characteristics of substance and as substance per se in space is almost absent, it is difficult to speak about space temperature in understanding, habitual for us. Nevertheless, you should not neglect the fact that outside the planetary and star atmospheres there are particles of dust, a gas molecule, streams infrared, ultra-violet, X-rays, etc.
It is necessary to notice that temperature in space can vary very strongly. Traditionally was considered that it is equal to absolute zero, i.e. 0 degrees Kelvin or-273.15 degrees Celsius. However actually the subject left in outer space provided that will not influence it radiated by stars warmly, will be cooled (or will heat up) up to the temperature of 2.725 degrees Kelvin or-270.425 degrees Celsius. It is caused by influence of relic radiation.
Relic radiation is an electromagnetic space radiation with a range which is characteristic of absolutely black body with a temperature equal to 2.725 degrees Kelvin. It appeared even at the time of origin of the Universe though then its temperature was much higher, than now. It is caused by gradual decrease in temperature of photons which movement on speed limit and is relic radiation. It extends rather evenly therefore the difference of temperature of a relic background in different sites of space if changes, then it is insignificant. It means that it is possible to assume as a basis space temperature, a component of 2.725 degrees Kelvin.
However it is impossible to forget about the thermal radiation of stars. As the vacuum is a fine heat insulator, and in space there is no atmosphere and grow. Thus, space is hot and cold at the same time depending on in what point it is measured. Far from stars where the heat flux almost does not get, it will be equal to about 2.725 degrees Kelvin as relic radiation is evenly widespread in all Universe, available to studying terrestrial astronomers of a part, but at approach to a star will gradually increase.