Lippert, 42, suffered deep gashes to his cheek and hand when he was assaulted by knife-wielding nationalist Kim Ki-Jong at a breakfast function in central Seoul last month.
The envoy required 80 stitches to the wound on his face and two-and-a-half hours of surgery.
The prosecutors' office in Seoul said Kim, 55, was charged with attempted murder, violence against a foreign envoy and obstruction of duty.
Kim, 55, was a known maverick activist who had been handed a two-year suspended sentence in 2010 for hurling a rock at the then Japanese ambassador to Seoul.
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"There was an intention to murder because (Kim) used a lethal weapon in a pre-meditated crime to attack the ambassador's face and neck repeatedly," it said.
Kim has told investigators the ambassador was the "symbolic" target of his opposition to annual US-South Korea joint military exercises, which he blames for blocking dialogue with North Korea.
The annual drills have long been condemned by Pyongyang as rehearsals for invasion.
Kim insisted he had acted alone and not on the orders of Pyongyang, but prosecutors said they were looking into whether he has violated the South's strict National Security Law banning any act seen as aiding North Korea or promoting its ideology.
Kim had visited the North seven times and once tried to erect a memorial in Seoul to the late North Korean leader Kim Jong-Il after his death in 2011.
North Korea has rejected accusations that it may have been behind the attack as a "vicious" smear campaign by Seoul.