When designing wooden structures and furniture, it is very important to consider joints that allow the structure to stay together and upright. There are many different types of wood joints. The selection of a joint type and its properties are some of the most important design choices. This article was dedicated to the Domino joint, which allows for strong joints. The Domino joiner is a loose tenon and mortise manufacturing joining tool. This article discusses the effect of selected parameters, such as the type of stress (tensile and compressive), size of the Domino joiner (one-half and one-third thickness), wood species (beech (Fagus sylvatica L.) and spruce (Picea abies L.)), and adhesive type (polyvinyl acetate and polyurethane), on the joint stiffness. The influence of the annual rings was also monitored.