As part of its protest, Codepink created a hoax version of the top Aipac spokesman's email address and sent out a press statement calling on Israel to stop building new settlements.
The hoax was was picked up by Al Jazeera's English service a well as US news organisations such as National Public Radio and ABC.
"Aipac calls on the Netanyahu government to make a conscious effort to move away from actions that create tensions between the two governments and undermine prospects for Israel-Palestine peace," said the fake statement.
"Aipac supports policies of aggression that damage Israel's reputation, harm innocent Palestinians"
Medea Benjamin, a Jewish-American activist from Codepink
"Aipac therefore calls on the Israeli government to immediately freeze new settlement projects, both in the West Bank and Jerusalem."
Codepink's other protests this week have included daily morning protests, staging of a checkpoint for attendees, and an afternoon press conference announcing the launch of a city-wide boycott of products made in the settlements.
The activists say they are outraged at the influence that Aipac has on US policy.
"Aipac supports policies of aggression that damage Israel's reputation, harm innocent Palestinians, and contribute to making America less safe in the world," Medea Benjamin, a Jewish-American activist from the group, said.
With the new tension between the US and Israeli over the Jewish state's latest announcement to build 1,600 more settlements in occupied East Jerusalem, the activists believe that now is the time to protest Aipac's influence on US foreign policy in the Middle East.
"The timing is right to break the detrimental influence of Aipac, which demands unquestioning public and financial support for Israel despite its illegal actions," Rae Abileah, a Jewish-American Codepink organiser, said.
Codepink has condemned Aipac's silence on the illegal settlements and the continued US military aid to Israel, which was used in the attack on Gaza last year, which it said broke international law.
The announcement of Israel's plan to build more settlements triggered outrage from the Palestinians and halted recently-agreed US-brokered indirect talks between Israelis and Palestinians, even before they got started.
In his speech to Aipac, Netanyahu blamed the Palestinian Authority for not wanting to negotiate.
The plan for more settler homes also drew sharp criticism from Barack Obama, the US president, and Hillary Clinton, the US secretary of state, who reiterated that criticism in her speech to the Aipac committee earlier on Monday.
Palestinians want East Jerusalem, which Israel captured along with the West Bank in the 1967 Middle East war, as the capital of a future state.