The vote was an embarrassing setback for Obama, who favors both measures. It revealed divisions with the Democratic Party over the president's signature trade agreement, a keystone of his foreign policy shift to Asia.
Many Democrats and labor unions fear the TPP could cost American jobs as employers chase lower costs in signatory countries. Ahead of Friday's vote, the AFL-CIO labor group urged Democrats to oppose the worker aid portion of the single bill as a way of defeating fast-track.
On Wednesday, House and Senate Republican leaders committed to breaking off the worker aid component and holding separate votes on it.
At the White House, in an effort to rally support within his own party, Obama met pro-trade Democrats, who arrived by bus ahead of a picnic for members of Congress.
Later, in remarks at the picnic, the president made reference to the tension over the issue without specifically mentioning trade.
"Obviously, democracy can be contentious," Obama said. "There are times where people have deep principled disagreements, but I hope that events like today remind us that ultimately we're all on the same team."