This study evaluates the price differences between voting and non-voting shares of a representative set of Brazilian companies traded on the São Paulo Stock Exchange from 1995 to 1999, assessing also the impacts of the amendments in the Brazilian Corporate Law that take place in 1997. The tests showed that, due to these changes, for most companies a downtrend occurred in the price differences, and, as time passed, the voting share was usually trading at a discount to the non-voting share. After identifying in the literature some key variables that influence these prices differences, we used some cross-section regressions for each year of the period to test the model with explicatory variables related to the liquidity, capital structure and shareholder composition of each company, as well as dividends paid to each class of share. The models tested were statistically significants for the whole period, explaining partially these price differences. The results of the regressions for each annual period showed that, after 1996, the models presented satisfactory results, with better results and degrees of confidence after 1998. The liquidity variables and the variable that represents the controller`s ownership of non-voting shares were the ones that showed the better degree of confidence during the period. The linear coefficients of the liquidity variables were positive, as expected, representing the correlation between these measures and the price differences between voting and non-voting shares. New changes in the corporate law are being studied and may affect the price differences between voting and non-voting shares and the valuation of all the stock market, representing an interesting subject to future studies.