Objectives:
This cross-sectional survey research aimed to analyse the multi-level factors which influence the access to tobacco among youth in Thailand.

Methods:
Stratified random sampling was applied to select samples for survey and 12 provinces were selected from 4 regions Thailand. The sample consist of 3,600 secondary school students, 3,600 student’s parents, 360 teachers, 360 community leaders, 1,200 tobacco retailers, and 60 provincial tobacco product control committees. The data were collected by self-administered questionnaires and analysed by descriptive statistics and hierarchical linear model using Mplus version 7.11.

Results:
The results showed that 20.10% of the secondary school students had smoked in the past 30 days, most of them smoked the manufacturing cigarettes (55.12%), followed by roll-your-own cigarettes and electric cigarettes equally (18.11%). They bought the cigarette themselves from the grocery stores and convenience stores (63.75%). The multi-level factors influencing youth access to tobacco at statistical significance of 0.05 consist of the positive attitude towards smoking (β= 0.109, p < .001), the perceived risk of disease (β = -0.096, p < .001), subjective norms (β= 0.061, p = .042), and the perceived marketing strategies in the tobacco industry (β= -0.060, p = .036), getting social support from parents (β= -0.069, p = .002), getting social support from teachers (β= -0.067, p = .029), getting social support from community (β= -0.094, p = .001), and non-smoking community operation (β= -0.275, p < .001).

Conclusion(s):
The results of this research suggest that government agencies should strengthen law enforcement on restricting access to tobacco of youth under 20 years of age and provide activities to change youth attitude and perception towards smoking by focusing on the participation of parents, teachers and the community.