in Star-cd there are some reference data i am a little confused.

while we input reference date , for example:

reference pressure :1e5 cell number of ref. pressure :1 reference temperence :273 reference density:1.205

does it means ? In cell no.1 pressure = 1e5 temperence = 273 density = 1.205

if not, what's the meaning of ref. density and ref. temperature. Will these two number effect the calculation?

With your reference values you set the relative level. When you load your post data you can specify absolute or relative. This relative is related to your reference value. In the inkompressible case where you just calculate dp/dx it is not so important but in the kommpressible case it is important to choose the correct numbers cause you calculate your thermodynamic numbers based on the local values. The boundary conditions you specify are also related to your refference values, so take care what numbers you use and have a closer look to the manual cause there is everytihing written what you have to know about it.