With the ongoing growth of social media, social media influencers are gradually playing a critical role in the marketing plan of organisations. While most companies are keen to employ influencers to generate profits and gain market share, only a few studies have discussed how social media influencers can contribute to non-profits or social activities, which inspires the present study to explore the mechanism of online influencers endorsing social problem campaigns. Based on that, this research has two main objectives: 1) to examine what impression management tactics have been utilised by social media influencers; and 2) to identify consumers’ responses to those tactics. This research chose qualitative case study approach which uses the Asian hate as the case. Content analysis was adopted to analyse Instagram posts of eight social media influencers and the comments of their followers in relation to those posts. I have found two dominant tactics, which are Solution and Campaign- promotion, and two supplement tactics, including Supplication and Association. In accordance with these tactics, the audience revealed five themes of responses: Educated, Feelings, Support, Resonance and Seeking reasons. The analysis revealed Solution as one of the leading tactics that will trigger people to feel educated and be supportive of the campaign posts, while Campaign-promotion will provoke Resonance, Reasons seeking and feeling Educated. The findings of this dissertation enrich the knowledge of impression management theory and tactics. It also encourages policy makers and social marketers to formulate appropriate policies to deal with social problems and adopt influencers as a tool to promote social cause.