A blind mortise and tenon joint is a type of woodworking joint used to join two pieces of wood at right angles, where the tenon (a protruding piece on one piece of wood) fits into a mortise (a corresponding slot or hole in the other piece of wood). The term "blind" refers to the fact that the end of the joint is not visible from the outside of the assembled workpiece.

In a blind mortise and tenon joint, the tenon does not extend through the full thickness of the piece of wood, but rather stops short, leaving a portion of the mortise unexposed. This type of joint is commonly used in furniture making and joinery where a clean, seamless appearance is desired, as it hides the end of the tenon within the mortise.