"Our parties may not see eye to eye on everything, but we must agree on this: the Democratic Progressive Party is not your enemy, but the party on the other side of the Taiwan Strait is," Chen said.
Ma agreed that the DPP and his Kuomintang party should avoid confrontation and concentrate on improving the economy, the Taipei Times reported Tuesday.
The two-hour meeting was broadcast live on Taiwan television stations. Chen agreed to the debate as his popularity fell and Ma's rose after a high-profile trip to the United States.
But the talks did little to narrow differences between the two leaders.
Ma called for maintaining the status quo in cross-straits relations and engaging in talks with Beijing under the "1992 consensus" that says there is only one China. He said Taiwan should "act as a peacemaker rather than as a trouble maker" in the Asia-Pacific region.
Chen said no consensus was reached in 1992, and that Beijing's view of "one China" means the People's Republic of China. "There should not be the one-China principle," he declared.