New Left Review
Still arguably one of the best journals from the left on a wide range of topics including: “world politics, the global economy, state powers and protest movements; contemporary social theory, history and philosophy; cinema, literature, heterodox art and aesthetics.”

Capital and Class
Since 1977 Capital & Class has been the main, peer-reviewed, independent source for a Marxist critique of global capitalism. [Archive]

Historical Materialism
One of the best interdisciplinary journals dedicated to exploring and developing the critical and explanatory potential of Marxist theory.
An excellent resource for all people who wish to fight to improve their lives, their communities and their working conditions.

A journal, “primarily oriented towards conceptualising the conditions of possibility of a communist overcoming of the capitalist mode of production—and of the multiple structures of domination which pattern societies characterised by that mode of production—starting from present conditions.”

An Introduction to the Three Volumes of Karl Marx’s Capital
by Michael Heinrich [Translated by Alexander Locascio]
One of the best and most accessible introductions to Marx’s critique of political economy.