A three-dimensional nonlinear baroclinic model is used to verify the circulation in the Ballenas Channel (Gulf of California) deduced from observations, which concluded that the cold SST of the channel is due to the deep inflow of water over the sills at both ends of the channel; this convergence at depth would lead to upwelling (divergence) in the upper layers, and to surface outflow through both ends. Here it is reported that the deep flow from the south does enters into the channel but not that from the north. The deep inflow returns back mainly along the surface through the same southern end of the channel and a small fraction flows out through the northern end of the channel and between ¿ngel de la Guarda and San Lorenzo Islands. The bottom flow that enters through San Esteban sill does not go all the way along Tiburon and Delfin basins and into Ballenas Channel through the northern sill; instead, it returns in the intermediate and surface layers after mixing in those basins.