In the present work we have studied ion transport and their correlation with network structure of Li2O-P2O5 glasses. We have measured the ac conductivity of the glasses for wide ranges of temperature and frequency. The conductivity shows a crossover from dc to dispersive behavior with the increase in frequency. We have observed that the dc conductivity and the crossover frequency obey Arrhenius relation with same activation energy. We have calculated characteristic lengths of ion transport, such as the characteristic mean square displacement of mobile ions and the spatial extent of localized motion, within the framework of linear response theory. We have observed that both the length scales decrease with the increase in Li2O content in the glasses. We have also investigated FTIR and Raman spectra to study the structure of glassy network and established a simple correlation between transport properties and network structure of the glasses.