The study intends to investigate how social media characteristics impact on each stage of the consumer buying decision process in the Sri Lankan context. For the study, a quantitative research method was used, and a sample of 147 respondents was selected by snowball sampling method. Primary data was used for achieving research objectives and self-administered, structured questionnaires were used for the data collection. The research reveals that social media characteristics influence on all the stages of consumer buying decision process while the biggest impacts are on post- purchase stage, information stage and evaluation stage respectively. The research explains the role of social media as a current trend, impact of social media on consumer buying decision process and implication for marketers.