Varro proved to be a highly productive writer and turned out more than 74 Latin works on a variety of topics. Among his many works, two stand out for historians; Nine Books of Disciplines and his compilation of the Varronian chronology. His Nine Books of Disciplines became a model for later encyclopedists, especially Pliny the Elder.

Varro`s only complete work extant, Rerum rusticarum libri tres (Three Books on Agriculture), has been described as "the well digested system of an experienced and successful farmer who has seen and practised all that he records."

The compilation of the Varronian chronology was an attempt to determine an exact year-by-year timeline of Roman history up to his time.

Varro was recognized as an important source by many other ancient authors, among them Cicero, Pliny the Elder, Virgil in the Georgics, Columella, Aulus Gellius, Macrobius, Augustine, and Vitruvius.

One noteworthy aspect of the work is his anticipation of microbiology and epidemiology. Varro warned his contemporaries to avoid swamps and marshland, since in such areas “...there are bred certain minute creatures which cannot be seen by the eyes, but which float in the air and enter the body through the mouth and nose and cause serious diseas.”