Conservative treatment is the basic treatment option in humeral fractures. The most important issue in patients treated with brace or splint is close follow-up of the patients. Due to the mistakes during conservative treatment or deformities developing after muscle tensions, non-union could rarely be observed. Nonunion rates are higher after surgical treatment. Nonunion could be atrophic or hypertrophic. While basic problem in atrophic non-unions is biological, it is stability deficiency in hypertrophic non-unions. The main treatments in atrophic non-unions are refreshing the fracture fragments, compression of the fracture line, and grafting. In hypertrophic non-unions on the other hand, developing the stability usually ends up with union.