Nanotechnology is the key solution for many human problems such as energy conversion, water treatment, and material science. In composite materials, nanoparticles are dispersed in a matrix material such as metals, ceramics, or polymers to enhance their mechanical and thermophysical properties. Polymer nanocomposite materials found their applications in vital fields such as the automotive and aircraft industries. There are many techniques adopted to produce polymer nanocomposites, and they are summarized and discussed according to our best known in this paper. All techniques aim to produce nanocomposite materials with uniform dispersion and without aggregations. Melt-mixing, mixing, in-situ polymerization, electrospinning, and selective laser sintering techniques are the most commonly used techniques to produce polymer nanocomposite. The utilization of water, atomic layer deposition, and plasma-assisted mechanochemistry are found to eradicate the issue of nanoparticles aggregation for melt-mixing technique. Also, sonication with high frequencies plays the same role for mixing techniques. In-situ polymerization provides fabrication of nanocomposites that are thermodynamically stable. Electrospinning represents an effective method which is suitable for producing porous structures. In addition, fabrication of nanocomposites via selective laser sintering has obvious benefits to overcome the problem of aggregation. The working principles of each technique, including the advantages and disadvantages, are discussed.