Due to the major shift in online purchasing during the COVID-19 lockdown, celebrity endorsement marketing has gained traction. Concurrently, COVID-19 has also transformed consumers' attitudes toward using eco-friendly products, such as green skincare products, to ensure a healthier lifestyle. This study developed a comprehensive framework based on the stimuli-organism-response theory and the parasocial interaction theory to empirically evaluate the impact of celebrities' credibility attributes and consumers' interests in celebrities on their attitudes towards advertisements for endorsed green skincare products, their intentions to make a purchase, and their willingness to pay a premium price for these products. 778 Malaysian consumers participated in the online survey, and their responses were analyzed using partial least squares structural equation modelling (PLS-SEM). The results showed the positive effects of credibility traits (trustworthiness – β = 0.100, p-value = 0.026; exquisite personality – β = 0.075, p-value = 0.028; dignified image – β = 0.152, p-value = 0.001; expertise – β = 0.221, p-value <0.001), and customer attention to celebrities (β = 0.184, p-value <0.001) on their attitudes toward endorsed advertisements. Likewise, credibility features (exquisite personality – β = 0.116, p-value = 0.002; dignified image – β = 0.112, p-value = 0.017; expertise – β = 0.207, p-value <0.001) and customers' companionship with celebrities (β = 0.142, p-value = 0.001) also have a significant positive impact on attitudes towards brands. Finally, consumers' purchasing intentions and willingness to pay premium prices for green skincare products were strongly influenced by their attitude toward advertising (β = 0.484, p-value <0.001) and brands (β = 0.326, p-value <0.001). Evidently, the findings of this study may help players in the cosmetics industry enhance their marketing and promotion tactics for eco-friendly beauty and personal care products.