Mobile phone is a small, portable communication device that enables people to make phone calls whenever where they are. All mobile phones operate in the radiofrequency range. Hence all mobile phones emit radio frequency radiation. Exposure from the antennas is continuous (very low) irradiates the whole body and exposes entire community. Therefore the exposure to low level radiation for long term will lead to some biological hazards. The aims of the study are to assess the impact of smart phone usage among college students and to evaluate the impact of smart phone usage and quality of sleep among college students. A descriptive study was chosen to assess the impact of smart phone usage and sleep quality. The study was conducted among 100 students in Saveetha Institution of Medical and Technical Science involving both Male and females students who fulfilled the inclusive criteria. Convenient sampling technique was used. The present study results show that shows out of 100 samples 10 (10%) had normal, 39 (39%) samples had mild questionable impact of smart phone using, 49 (49%) sample had moderate questionable impact of smart phone using, 2 (2%) had severe questionable impact of smart phone use. While coming to the quality of sleep 46 (46%) samples had good sleep quality, 28 (28%) samples had fairly good sleep quality, 10 (10%) samples had fairly poor sleep quality, and 6 (6%) samples had sleep quality. The study suggests that there should be limitation in using the smart phones and hazards should be highlighted by the health professional to the students.