Well since you did not add any information so any of us could help you. I will try on the limited information you provided.
1) Have you used this printer before successfully?
2) Can you ping the printer?
3) Open /Applications/Utilities/Printer Setup Utility. Highlight then printer then select 'Printer Setup Utility pull down menu and select 'Reset Printing System' This will reset the printing system and you will then have to re-add the printer. See if that works?
4) Have you checked the printer to see if it is not out of ink, still on, still connected the network?
5) What does you system admin say about the printer? Is it a hardware failure on the printer?
Please next time provide the OS X version, Computer setup, specs and printer model, plus how is it connected to the Mac.