Anna Trebunskaya -- Hurls at 'DWTS' After-Party

'DWTS' dancing pro Anna Trebunskaya looked fabulous when she arrived at the big after-party at Beso Tuesday night, but an hour and 40 minutes later she was puking her brains out.

Anna beat a hasty retreat just after 11 PM but lost it at the front door. The gnarliest part ... she's wiping her mouth when someone asks her for an autograph and she obliges.