The ground state properties of the strong coupling bipolarons in a parabolic quantum dot are studied based on the LeeLowPinesHuybrechts variational method. The law of the effective potential Veff of the strong coupling bipolarons changing with the strength of the electronphonon coupling α, the relative distance between two electrons r, and the radiu of quantum dot R0 are derived. The results show that Veff consists of three parts: Coulomb potential Vcoul, confining potential Vconf and induced potential Ve-LO. Ve-LO is always less than zero, and the absolute value |Ve-LO| increases when the strength α, and increases when the relative distance r between the electrons and guantum dot′s radius R0 decreace. The absolute value |Veff| increases with the strength α increasing and increases with the relative distance r decreasing. α and r are the main factors to influence the effective value. However, the quantum dot′s radius R0 and the dielectric constant ratio η have little influence on the effective potential Veff.