A laboratory trial was carried out to determine the behavior of different fining agents in samples of white wine obtained from various grape varieties. These tested wines were produced in two regions of the State of São Paulo and one of Minas Gerais. It was observed that these fining agents behaved differently according to the type of wine to be cleared. In our experimental trials bentonita was the best fining agent. These observations agree with those obtoined by others authors in other parts of the world. As a general procedure it is advisable to conduct small-scale fining tests in the laboratory before attempting to clarify the bulk volume of wine in the winery, to determine the efficiency of the fining agent, its effect on the wine, and the quantity necessary to clarify.