The crowd, made up of mostly young men who support Hezbollah and allied political parties, hurled stones at riot police near the embassy, from which they were separated by layers of barbed wire. Some protesters tried to remove the wire, at which point they were sprayed with water cannons.
The protesters burned American flags and mock-up dollar bills, calling the US the "mother of terrorism." The riot police eventually escorted the crowd away from the embassy area, Naharnet website reported.
This is the second anti-US protest in Beirut and its suburbs this week amid strained US-Lebanese relations.
Lebanon is facing its worst economic and financial crisis, which has triggered anti-government protests and created domestic political tension between rival groups.
Hezbollah Secretary General Sayed Hassan Nasrallah recently blasted comments by US Ambassador Dorothy Shea criticizing his group and said Washington was seeking to turn public opinion against Hezbollah.
Dozens of Lebanese also protested Wednesday near the Beirut airport, on the day General Kenneth McKenzie, the commander of the United States Central Command, visited Lebanon. The protesters denounced his visit and chanted "Death to America."