In this talk, we show the Fisher information associated with entanglement-assisted coding has a monotonic relationship with the logarithmic negativity for certain classes of continuous variable quantum states of practical significance. For the two-mode squeezed states and photon-subtracted squeezed states, those values are uniquely connected by an identical equation in a fairly good approximation. For entangled qubit states, similar relationship also holds. We discuss the entanglement quantification via the Fisher information, which is experimentally accessible without full quantum state reconstruction.