We perform a full amplitude analysis of the process e+e−→J/ψD¯D, where D refers to either D0 or D+. A new charmoniumlike state X∗(3860) that decays to D¯D is observed with a significance of 6.5σ. Its mass is (3862+26−32 +40−13) MeV/c2, and its width is (201+154−67 +88−82) MeV. The JPC=0++ hypothesis is favored over the 2++ hypothesis at the level of 2.5σ. The analysis is based on the 980 fb−1 data sample collected by the Belle detector at the asymmetric-energy e+e− collider KEKB