The objective of the present study is to examine the sociodemographic determinants of amount of smoking knowledge in Malaysia. Data are obtained from the Global Adult Tobacco Survey (GATS). The GATS uses a multistage stratified sampling. A total of 4,153 respondents are used for analyses. The effects of sociodemographic factors on smoking knowledge are examined using a negative binomial regression. Age, wealth index, education, ethnicity, house locality, and smoking behavior are significantly associated with smoking knowledge. In particular, there are negative relationships between smoking knowledge and higher wealth index, less-educated individuals, Chinese, rural dwellers, and smokers. The present study concludes that sociodemographic factors play an important role in determining smoking knowledge. Hence, as an intervention measure directed toward improving the knowledge of smoking among Malaysian population, effective policies should pay special attention to individuals who are likely to have poor information on smoking.