In this thesis, searches for narrow resonances decaying into pairs of vector bosons (WW, WZ and ZZ) are presented. The searches are performed using 20.3 fb-1 and 3.2 fb-1 of proton-proton collision data collected with the ATLAS experiment at the LHC at centre-of-mass energies of 8 TeV and 13 TeV, respectively. Events are selected in the fully hadronic final state, characterised by two large-radius jets. Requirements on the jet mass and substructure variables are imposed to select large-radius jets that are compatible with the hadronic decay of highly boosted W or Z bosons. In the absence of a significant deviation from the background prediction, exclusion limits at 95% confidence level are set on the production cross-section times branching ratio for three benchmark models: a bulk Randall-Sundrum model, an extended gauge model and a heavy vector triplet model.