The theme of this research is the influence of Romano Guardini s thought on the construction and development of Joseph Ratzinger s liturgical theology. It is part of the research activities of the Postgraduate Program in Theology of PUC-Rio, Area of Concentration Systematic-Pastoral Theology, research line Faith and Culture, research project Joseph Ratzinger s Theology and the Magisterium of Benedict XVI. The main objective is to investigate the existence of an internal coherence between the thinking of the veronese intellectual and that of the bavarian theologian in such a way that it can be verified whether Joseph Ratzinger s liturgical theology is in continuity with Romano Guardini s thinking about the sacred liturgy. Thus, after a first reflection that seeks to recover the personality and thinking of Romano Guardini from the presentation of biographical data, the historical / theological context and the exposition and analysis of his classic liturgical work The Spirit of the Liturgy, the study develops in two successive approaches: the presentation and analysis of the principles addressed in the famous ratzingerian writing The Spirit of the Liturgy; and the comparative analysis of the theological texts already cited, in order to discover points of contact between the thought of both authors, which examine the hypothesis that part of Joseph Ratzinger s liturgical thought is built on foundations laid by Romano Guardini. The scope of this research is to contribute to a better dissemination and understanding of the liturgical theology of Joseph Ratzinger.