The application of Linear Friction Welding (LFW) to aerospace Ti-alloys components offers significant weight reduction and cost saving advantages. The severe thermomechanical deformation associated with LFW results in a localised, yet complex microstructural development, which is the subject of the present investigation. In this work, the influence of LFW process parameters (pressure, amplitude, and frequency) on the as-welded and post-weld heat-treated microstructure and microhardness development in beta-forged Ti-6246 was investigated. Metallurgical characterisation of the welds was performed using optical, scanning and transmission electron microscopy, and microhardness. The microstructural and microhardness developments were correlated to the heat input and process variables. It was found that the thermomechanical deformation in the weld resulted in the formation of dynamically recrystallised metastable ?-phase in the weld, which indicates that welding at the weld line occurred above the beta-transus regardless of welding parameters. However, the width of this region was found to be dependent on the process parameters, as revealed by microstructural and mechanical characterisation.