In photovoltaic (PV) power generating systems DC-DC converters acts as an interface between the PV source and the load. This paper deals with the use of a high voltage gain three-phase interleaved DC-DC boost converter (IBC) for the standalone PV system applications. Interleaving technique provides high power capability and reduces the voltage stress on the power semiconductor devices. In PV system maximum power point tracking (MPPT) technique is used to track the maximum power from the PV panel. To extract the maximum power from the PV panel at different irradiation levels radial basis function network (RBFN) based MPPT algorithm is developed. The output power of the high voltage gain three-phase IBC with RBFN based MPPT controller is compared with traditional P&O and fuzzy logic based MPPT controllers at different irradiation levels. The performance analysis of P&O, fuzzy logic and RBFN MPPT algorithms with high voltage gain three-phase IBC is done by using MATLAB/SIMULINK. © 2018, Gazi University Eti Mahallesi. All rights reserved.