The methods of increasing heat transfer are current topics in the field of heat transfer in heat exchangers. The most important methods used to improve heat transfer are the use of nanofluids, changing the shape of the channel body, using porous materials, and using baffles in the flow path. The change in the shape of the channel body from a flat wall to a wavy wall causes heat transfer in heat exchangers. Therefore, the innovation of this research is the use of a baffle in the middle of the channel with a wavy wall to change the shape of the flow lines and fluid turbulence. The aim of this research is to simultaneously investigate the effect of using nanofluids, wavy walls, and baffles on heat transfer using computational fluid dynamics. For this purpose, the effect of Reynolds number, wall wavelength, and water-titanium oxide nanofluid concentration on heat transfer was investigated, assuming laminar, steady, and continuous flow. The channel simulation was performed in two dimensions using Ansys CFX2023R1 software. The results showed that in a channel with corrugated and baffled walls, using a nanofluid with a lower concentration (φ=0), higher flow velocity (Re=500), and a wall with a shorter wavelength (λ=12mm) resulted in a larger Nu number.