The Roman Catholic Church's response to the Protestant Reformation is commonly known as the Counterreformation or the Catholic Reformation. It consisted of attempts to improve the Catholic Church as well attempts to reassert the authority of the Church and the rightness of its doctrines.
Many in the Catholic Church had believed for a long time that the Church needed to reform itself. In response to these beliefs (and to the Protestant Reformation), the Catholic Church did such things as trying to improve the training of priests and trying to get monastic orders to reform themselves and become more attentive to spiritual concerns. In other words, it tried to make the Church get back to being a true spiritual entity rather than something that was more concerned with temporal power and wealth.
At the same time, however, the Church fought back against many of the ideas of Protestantism. It reasserted the power of the pope and the importance of sacraments and it attacked many Protestant doctrines such as the idea of salvation through grace alone.
So, in response to the Reformation, the Catholic Church tried to make itself more responsive to the spiritual needs of its people but also to reassert its authority.