A 3D metal-organic framework (MOF), [Zn(BPHY)(SA)](n) (1; BPHY = 1,2-bis(4-pyridyl)-hydrazine, H(2)SA = succinic acid), which crystallizes in a noncentrosysmmetric space group (Cc), has been solvothermally obtained and testified to be a good nonlinear-optical material with the largest second-harmonic-generation response among the known MOFs based on sysmmetric ligands and high stability. Ultraviolet-to-visible tunable emission for 1 is observed.