Objectives To explore how cigarette packet branding and colours influence young male smokers’ perceptions of tobacco brands in Cambodia.

Design Mixed-methods study.

Setting Worksites, living accommodations, a university and public locations in Phnom Penh, Cambodia.

Participants 147 male Cambodian smokers (18–24 years).

Interventions Participants were shown mock-up pictures of different cigarette packet branding and colour variations and asked to respond to close-ended and short-response questions.

Outcome measures Brand recognition, appeal and harm perceptions of cigarette packet branding and colours.

Results When shown three packets with brand names removed, 98.6% of participants recognised packet one as Mevius brand, 21.1% recognised packet two as Marlboro and 38.8% recognised packet three as 555. For the three fully-branded and three matching plain packets, most participants selected a fully-branded packet as the most appealing taste (83.0%) and most appealing to youth (81.7%). Participants described their chosen brand as appealing due to beliefs about its superior taste/quality, reduced harm and symbolic attitudes surrounding tobacco brands and smokers of different brands in a social status hierarchy. When shown six different colours of unbranded packets, participants selected the blue packet (51.0%) as the most appealing for taste, the white packet as the least harmful (25.2%), and the red (15.0%) and black (12.9%) packets as the most harmful to health. They described their associations of packet colours with abstract imagery concerning smoking-related harms and their future well-being.

Conclusions Findings suggest that packet branding and colours influence young male smokers’ recognition, appeal and harm perceptions of tobacco brands in Cambodia and remain an influential marketing tool for tobacco companies where advertising is banned. Consequently, Cambodia and other low and middle-income countries in Southeast Asia should implement plain packaging.