The use of polyethylene gels to adhere high strength and high modulus polyethylene fibers together has been investigated. It was found that the joint strength obtained using high density polyethylene (HDPE) gel in decalin or tetralin depended on the heating temperature and time of the gel. When heated at 100 degrees C for 30 min, the gel showed such a high joint strength that polyethylene fibers were torn, and this should be enough for practical uses. The results of the present study demonstrate that utilization of the polyethylene gel as an adhesive is an extremely effective method when polyethylene fibers are used in composite materials.