In a statement, the bank said it intends to "vigorously contest" the enforcement of the so-called John Doe summons, citing Swiss financial privacy laws, which it says must be taken into account under international comity principles.
UBS says Swiss law protects information being disclosed even thought the accounts all belong to US citizens.
The Internal Revenue Service (IRS) wants to identify the wealthy account holders because they have violated US tax law by hiding their assets with UBS.
The Swiss bank has already accepted "full responsibility" for helping conceal the money and has agreed to pay a $780 million fine. However, it is not about to identify those it assisted.
Acting assistant attorney general John DiCicco said it is "appalling" that with millions of Americans losing their jobs and homes, over 52,000 wealthy individuals have actively tried to "evade their civil and legal duty to pay taxes".
Based in Zurich, UBS has operations in over 50 countries.