The utility model discloses a combined pen. The combined pen comprises a plurality of pen units, wherein side walls of pen caps of the pen units are provided with slide rails and strip-shaped ribs respectively; the ribs are provided with sliding chutes of which the sizes are matched with the sizes of the slide rails; and adjacent pen units are slidably connected with each other through the slide rails and the sliding chutes. The pen units are connected together by matching the slide rails and the sliding chutes of adjacent pen units; and different pen units are selectively connected together according to demand so as to be convenient to store, carry and take for use. The connection mode of sliding chute and slide rail is simple and practical; the slide rails and the sliding chutes are closely connected together, so that the pen units have low probability of being separated. Through the combined pen, the defect that a plurality of pens are inconvenient to store and carry in the prior art is overcome.