Cyberbullying, an advanced form of bullying on the internet space has awakened the interest and concern of researchers as well as social media users in Nigeria. It is assumed to pose a threat to the lifestyle of social media users which prompts the study towards appraising the influence of cyber bullying on the lifestyle of social media users in University of Nigeria Nsukka and Imo State University. The study is to ascertain the existence of cyberbullying, its extent of influence and other factors responsible for a change in the lifestyle of social media users in UNN and IMSU. In conducting this study, the Media System Dependence theory was adopted which posits that the dependence of users on social media sites makes them prey to cyberbullying activities. The sample size of 331 was derived using the Taro Yamane formula from the population of post graduate students used to represent social media users in the selected institutions. A random sampling technique was adopted with structured questionnaires as the research instrument. The results were analyzed using frequency tables and percentages. 75% of respondents affirmed the existence and prevalence of cyberbullying which affects user’s lifestyle to a large extent and further prompts them towards taking actions as far as withdrawal from social media platforms, low self-esteem and exchange of ill intended messages to others as against the 25% of respondents who affirmed otherwise. The study recommends that the federal government as well as management of the diverse social media sites have a role to play in limiting if not entirely curbing the menace of cyberbullying.