Glass painting is a kind of drawing painted on the inside surface of transparent glass, executed with oil and hard resin or with watercolor and gum on glass sheets. Also known as reverse glass painting, engravings are laid down on the back of the glass, and painted from the reverse. The effect is one of stunning clarity and rich color ideally serving as a connoisseur's delight.

Major types of traditional stained glass paints are: vinegar trace paint, matt paint, silver stain, and oil-based paints. The process usually starts with etching a full size working drawing. Using this drawing as a template, the glass is selected and cut, and each piece of glass is individually painted using glass paint. The paint is then fired into the surface by heating the glass to approximately 650° centigrade in a furnace. When all of the glass has been painted it is assembled into lead panels.

Glass paintings have been a folk art tradition in Europe and North America and, from the 15th to the 18th century, and were regarded as a fine art in northern Europe, where they have been more recently revived. Traditionally stained glass painting referred to painting on the surface of a sheet of glass to be included in a stained glass work. This kind of painting, which is actually closer to drawing than painting, was done to add details such as faces and folds of clothing that couldn't be added with traditional lead lines. It was also used to cover up portions of stained glass works so that light was kept from shining through. As the 19th century progressed there was a revival of interest in the Gothic arts and the majority of designers reverted to the medieval techniques of producing mosaic stained glass, leading off separate colors. Different paint techniques and effects were employed within these various design styles, and were generally reliant on the media with which the paint was mixed. There have been several innovations since then, particularly in techniques of glass painting, which have both enriched and added to the variety and designs of stained glass that can be appreciated today.

Glass painting allows an expressive mix of form and dimension to be added to glass. Painters today coming up with fused elements in their paintings and offer contemporary paintings on a variety of topics. Decorated with a blend of sparkling light, the beauty of glass paintings is par excellence.