In a letter to President Barack Obama Thursday, Rice said, "I am fully confident that I could serve our country ably and effectively in that role. However, if nominated, I am now convinced that the confirmation process would be length, disruptive and costly – to you and to our most pressing national and international priorities."
Rice added, "That trade-off is simply not worth it to our country."
Rice recently came under fire from Republican lawmakers for her handling of information in the hours after the deadly attack on the U-S consulate in Benghazi.
ABC News reports that President Obama has accepted Rice's decision to remove her name from the running.
"While I deeply regret the unfair and misleading attacks on Susan Rice in recent weeks, her decision demonstrates the strength of her character, and an admirable commitment to rise above the politics of the moment to put our national interests first," Obama said in a written statement. "The American people can be proud to have a public servant of her caliber and character representing our country."