A solar cell is produced by dipping a multicrystalline silicon substrate 28 in a solution 24 containing silicon, growing a silicon layer on the substrate 28 while decreasing with time the temperature drop rate of the solution during the dipping of the substrate in the solution, and forming a pn junction in the silicon layer. Thereby, there is provided a silicon layer production method that can form a thick layer while restraining the degree of roughness, whereby a low-cost, multicrystalline-silicon solar cell production method is provided that realizes both a large current and a high FF.