Abstract—In this paper, four different topologies of soft-switching boost converter using a simple auxiliary resonant circuit for solar power system are reviewed. These converters have simple structure, low cost and ease of control and are applicable for photovoltaic applications. Also, these topologies raise efficiency and, minimize switching losses by adopting soft-switching method using resonance. As we know efficiency, number of components and, voltage and current stresses are effective in selecting the converter for different applications. Therefore we need to choose the optimal boost converter considering above indexes. Efficiency, number of components and voltage and current stresses of these soft-switching boost converters have been compared in this paper to choose the optimal converter for photovoltaic application.