Johann Nepomuk Paul Oischinger (13 May 1817 – 11 December 1876) was a German Roman Catholic theologian and philosopher who was a native of Witzmannsberg, Bavaria.
Oischinger studied theology and philosophy at the University of Munich, where he had as instructors Franz Xaver von Baader (1765–1841), Joseph Görres (1776–1848), Friedrich Wilhelm Joseph Schelling (1775–1854), Ignaz von Döllinger (1799–1890), Heinrich Klee (1800–1840), Johann Adam Möhler (1796–1838) and Franz Xaver Reithmayr (1809–1872).
In 1841 he received his ordination in Regensburg, and shortly afterwards returned to Munich, where he worked as a private scholar and journalist for the remainder of his career.
A number of his writings were harsh criticisms of medieval scholastic theology, in particular the belief system of Thomas Aquinas.
He was also the author of polemical writings aimed at contemporary movements that included Neo-Scholasticism and Güntherianism.