Reading Capital (French: Lire le Capital) is a 1965 book about Karl Marx's Capital, written by the French philosopher Louis Althusser and his students Étienne Balibar, Jacques Rancière, Pierre Macherey, and Roger Establet. The book was first published in France by François Maspero. An abridged edition was published in 1968, and a complete English translation in 2016.

Reading Capital is a key text of structural Marxism. It offers a philosophical re-reading of Capital as a scientific and theoretical work, rather than a text of humanist economics or historicist prophecy. The book introduced the influential concept of "symptomatic reading", a method of textual analysis that seeks to identify the unconscious, unposed theoretical problems within a text by examining its omissions and structural tensions. The authors critique empiricist, humanist, and Hegelian interpretations of Marx, arguing for an "epistemological break" in his thought around 1845, which separated his early, more ideological work from the scientific framework of his later writings. The book's publication history is complex; a heavily abridged French edition published in 1968 served as the basis for most international translations for decades, which significantly shaped its global reception by omitting several key essays.

Reading Capital originated in a seminar on Karl Marx's Capital held at the École normale supérieure in Paris during the 1964–65 academic year. The seminar was led by Louis Althusser, then a professor of philosophy at the school, and was collectively organized with his students Étienne Balibar, Yves Duroux, Jacques Rancière, and Jean-Claude Milner. The project was intended as a philosophical reading of Capital, an approach Althusser had called for in his earlier work, published in the collection For Marx. The result was a "collective work" in which each contributor, working independently, reached similar conclusions through different paths.

The project emerged in a specific political and intellectual context. The de-Stalinization that followed the 20th Congress of the Soviet Communist Party in 1956 had created an opening for new interpretations of Marxism that could challenge both Stalinist orthodoxy and the resurgent humanist readings of Marx that were gaining traction within the French Communist Party (PCF). Althusser's intervention was a "two-front war", opposing both the dogmatic scientism of dialectical materialism and the historicism and humanism of Marxists influenced by Jean-Paul Sartre and Georg Wilhelm Friedrich Hegel.

The papers from the seminar were collected and published in two volumes in November 1965 by publisher François Maspero, under the title Lire le Capital. The collection included contributions from Althusser, Balibar, Rancière, Pierre Macherey, and Roger Establet. Published as part of the 'Théorie' series edited by Althusser, the book was designed to oppose what Althusser saw as theoretical and political "opportunism" within the PCF. The publication was an immediate success in French academic and communist circles, establishing Althusser and his collaborators as prominent figures in Marxist philosophy.

In early 1968, Maspero approached Althusser about releasing a more accessible single-volume paperback edition. For this second edition, the contributions by Establet, Macherey, and Rancière's chapter "The Concept of Critique and the Critique of Political Economy from 'The 1844 Manuscripts' to Capital" were removed. This abridged version, containing only the revised essays by Althusser and Balibar, became the basis for most foreign translations, including the first English translation by Ben Brewster in 1970. This decision fundamentally shaped the international reception of the book. According to Nick Nesbitt, this abridged version led to a reception focused on Althusser's theory of ideology, while the "theoreticist, epistemological focus" of the original edition was largely dismissed or ignored. In France, a more complete four-volume paperback edition was published in 1973, which restored the previously excluded chapters. A complete English edition, translated by Ben Brewster and David Fernbach, was not published until 2016.

Reading Capital presents a philosophical interpretation of Capital, arguing that Marx's work constitutes a scientific revolution that breaks radically with all previous forms of political economy and philosophy. The book develops a series of concepts to articulate the specificity of Marx's scientific project, including critiques of empiricism, humanism, and historicism.

The book's most famous conceptual innovation is the method of "symptomatic reading" (lecture symptomale). Althusser derived this method from Marx's own reading of classical political economists such as Adam Smith. A symptomatic reading treats a text not as a simple expression of an author's thought but as a complex structure marked by "lapses", silences, and absences. The goal is to identify the text's "unsaid", which is not a hidden meaning but an "unposed problem" that the text implicitly addresses without being able to formulate. This technique, which Althusser drew in part from the psychoanalysis of Jacques Lacan, seeks to reveal the underlying "problematic"—the theoretical framework of concepts and questions—that governs a text.