Summary: We study quantum tunneling of a dipolar Bose-Einstein condensate in optical lattice when the spin system initially is prepared in a squeezed coherent state. It is found that there exists quantum tunneling between lattices \(l\) and \(l+1\), \(l\) and \(l-1\), respectively. In particular, when the optical lattice is infinitely long and the spin excitations are in the long-wavelength limit, quantum tunneling disappears between lattices \(l\) and \(l+1\), and that \(l\) and \(l-1\). Correspondingly, the magnetic soliton appears.