The popularity of social media and short-video platforms has made Kols (Key Opinion Leaders) the core channel for brand communication. When a large number of small and medium-sized Kols simultaneously produce homogeneous content within a similar period of time

a group public opinion phenomenon with large-scale dissemination power will be formed. This article conceptualizes it as the "KOL public opinion ant effect". This effect has a significant dual nature: when used reasonably

it can positively build a brand image

but once it triggers the concentrated spread of negative information

it may also lead to collective resistance within the circle

directly damaging the brand's long-term reputation. This study

based on Ellis' ABC Emotion Theory and Coombs' Situational Crisis Communication Theory (SCCT)

constructs a three-dimensional analysis framework of "information resonance - emotional resonance - action convergence". Through a dual case comparison and analysis of Perfect Diary (positive and active brand communication) and Xiaomi (negative and passive crisis response)

It reveals the communication mechanism of the ant colony effect in different public relations scenarios and the influence path of brand reputation. Research has found that the key distinction between positive and negative ant effects lies in whether a brand incorporates the "circle belief system" into the pre-consideration of public relations decisions - this directly determines whether the triggering event triggers collective seeding or collective resistance. This study contributes a reusable KOL group public opinion analysis model and a four-dimensional brand reputation governance system that includes "pre-event KOL stratified management - in-event public opinion monitoring and hedging - post-event crisis repair - long-term reputation co-construction". It provides a theoretical basis and practical path for enterprises to shift from passive "public opinion fire suppression" to active "public opinion co-construction" in the KOL-driven communication environment.