The Rheinische Zeitung was a 19th century German newspaper, edited most famously by Karl Marx.

The paper was founded on January 1, 1842 with a reformist pro-democracy editorial slant, providing an outlet for the Rhine region's middle-class and intellectuals, who were increasingly opposed to Prussian authoritarianism. Marx first published in the paper on May 5, 1842; his article against Prussian government censorship, published anonymously with the credit "by a Rhinelander," was widely lauded in the progressive community. He followed with more articles on the subject through the rest of May, producing a six-part series on freedom of the press. The positive response to this series served to increase the paper's circulation and influence.

In October 1842, Marx was named editor of the paper. On November 16, Frederick Engels visited the paper's offices on his way to England, meeting Marx for the first time and starting what would become a long period of collaboration between the two, lasting until Marx's death. Engels sent back a series of articles for publication in the Rheinische Zeitung from England, chronicling the conditions amongst the working class there; these would later be collected and published in his influential book, The Condition of the Working Class in England .

Under Marx's guidance, with additional influence from Engels, the paper began to take a more radical stance, openly opposing government policies with increasing stridency. An article by Marx critically discussing the relationship between the Prussian government and the Catholic Church was censored by the state and never published; several other of his articles opposing government policies were allowed to be published, but drew intense scrutiny.

By early 1843 Marx was promoting dangerously radical ideologies through the paper, increasingly espousing socialist and communist viewpoints and nearly openly calling for a revolution to replace the Prussian monarchy with a democracy. The Prussian government had heard enough -- on March 17, 1843 he was forced to resign his editorship, and the paper was shut down on March 31.