The Washington Post reported on Thursday that the senior official, who is suing the agency, was sacked in August "for unspecified reasons".
The lawsuit appears to be the first public instance of a CIA agent charging he was pressured to concoct intelligence on Iraq.
It claims the unidentified former agent was urged to produce reports in line with President George Bush's contention that Iraq had illegal chemical or biological weapons which threatened US and international security.
"Their official dogma was contradicted by his reporting and they did not want to hear it," attorney Roy Krieger told the Post of his client.
CIA spokeswoman Anya Guilsher told the daily she could not comment on the lawsuit, adding: "The notion that CIA managers order officers to falsify reports is flat wrong. Our mission is to call it like we see it and report the facts."
"Their official dogma was contradicted by his reporting and they did not want to hear it"
The ex-CIA agent's attorney
Krieger wrote a letter requesting a meeting with CIA Director Porter Goss due to "the serious nature of the allegations in this case, including deliberately misleading the president on intelligence concerning weapons of mass destruction", said the daily.
The US overthrew Saddam Hussein in April 2003, but has found no weapons of mass destruction in Iraq.
Washington has acknowledged some of its pre-war intelligence may have been faulty.
The plaintiff, whose identity is blacked out in the version of the lawsuit seen by the Post along with any reference to Iraq, is of Middle Eastern descent and worked 23 years in the CIA.
Many of those years were spent in covert operations collecting intelligence on weapons of mass destruction.
The lawsuit alleges the CIA investigated alleged sexual and financial improprieties by the agent "for the sole purpose of discrediting him and retaliating against him for questioning the integrity of the WMD reporting ... and for refusing to falsify his intelligence reporting to support the politically mandated conclusion" of matters that were blacked out".
Bush's team has been accused of
politicising intelligence on Iraq
Krieger told CNN that such accusations were common practice at the agency.
"In the past seven or eight years, I've represented probably in excess of 100 employees of the Central Intelligence Agency and in our experience when [someone] at the agency gets into disfavour or gets himself in a position of opposition to the agency, one of two things - sometimes both of them - happen," he said.
"Either he's subjected to a counterintelligence investigation based upon trumped-up allegations or he's referred to the office of inspector-general for investigation of his travel expenses, his finances and, in this case, payments made to an asset," Kreiger added.