Shouting "Undocumented, unafraid!" protesters sat down in a street adjacent to the Capitol and blocked traffic until police began handcuffing them and putting them into police vans.
Organisers said four undocumented immigrants were among those arrested, and that further civil disobedience actions were planned at Capitol Hill locations later in the day.
"Today we're hundreds, tomorrow we'll be thousands, and if we have to bring a million people to Washington DC we will do that, too," Democratic congressman Luis Gutierrez told the crowd.
Gutierrez has been instrumental in seeking to cobble together a broad reform plan in the House after the Senate passed comprehensive immigration legislation in June.
House leaders have said the lower chamber would ditch the Senate's approach and pass piecemeal bills separately addressing issues like border security and what to do with the so-called "Dreamers," undocumented children brought to the United States through no fault of their own.
"The urgency of the situation is too great," Eliseo Medina, a member of the Service Employees International Union who was arrested today, said in a statement.
"People are dying in the desert as they try to cross the border from Mexico, thousands of immigrants have been deported and every day families are being torn apart. We need to fix the system and we need to fix it now."
"We are angry that they are not producing action and we're willing to escalate to risk arrest and get arrested because what's happening is unjust," Kimberley Propeack, director of pro-immigration group CASA in Action, told AFP.
Congress goes on summer recess at week's end, and House members have shown little urgency about the issue despite a flurry of action earlier this year when a "Gang of Eight" senators unveiled their huge bill and helped push it through the Senate.
