Oil painting is the process of painting with pigments with a medium of drying oil as the binder. It has been the most common technique for artistic painting on wood panel or canvas for several centuries, spreading from Europe to the rest of the world. The advantages of oil for painting images include "greater flexibility, richer and denser colour, the use of layers, and a wider range from light to dark". But the process is slower, especially when one layer of paint needs to be allowed to dry before another is applied.

The oldest known oil paintings were created by Buddhist artists in Afghanistan and date back to the 7th century AD. Oil paint was used by Europeans for painting statues and woodwork from at least the 12th century, but its common use for painted images began with Early Netherlandish painting in Northern Europe, and by the height of the Renaissance, oil painting techniques had almost completely replaced the use of egg tempera paints for panel paintings in most of Europe, though not for Orthodox icons or wall paintings, where tempera and fresco, respectively, remained the usual choice.

Commonly used drying oils include linseed oil, poppy seed oil, walnut oil, and safflower oil. The choice of oil imparts a range of properties to the paint, such as the amount of yellowing or drying time. The paint could be thinned with turpentine. Certain differences, depending on the oil, are also visible in the sheen of the paints. An artist might use several different oils in the same painting depending on specific pigments and effects desired. The paints themselves also develop a particular consistency depending on the medium. The oil may be boiled with a resin, such as pine resin or frankincense, to create a varnish prized for its body and gloss. The paint itself can be molded into different textures depending on its plasticity.