Several different lasers have since been used in periodontics such as CO2, Nd: YAG, ER: YAG, Cr:YSGG etc. More recently, Diode Laser (GaAlAs)has been used in treatment of chronic periodontitis. One of the advantages of diode lasers in comparison to other laser systems, which is immediately apparent to the naked eye, is their size. The development of microstructure diode cells which are capable of emitting laser light has drastically reduced the bulk of laser systems. Diode laser has curettage and bio-stimulating effect. This eliminates the sulcular epithelium infected in a total and complete way than conventional methods of treatment, without any kind of damage to the underlying connective tissue and reducing the bacterial load, which easily penetrate within the sulcular epithelium. So, the aim of the present study was to evaluate and compare the effectiveness of diode laser (940nm) as an adjunct to non-surgical periodontal therapy in the management of patients with chronic periodontitis.