Roadway traffic control signs are commonly used to regulate, warn and inform road users. It is widely considered that traffic sign comprehension significantly affects traffic safety. The primary objective of this research was to investigate traffic sign comprehension among different types of road drivers of Bangladesh. To achieve the goals, 42 posted traffic signs were evaluated. Interviews of 402 drivers plying on four major road types were conducted using a questionnaire survey. The results showed that the drivers have a poor level of understanding of the meaning of the traffic signs. The overall comprehension level was about 67%. The percentages of drivers who correctly identified the regulatory, warning, and informatory traffic signs was within 66–69%. On average, 60–76% of the drivers were familiar with traffic signs. Drivers of the national highway and regional highway were found to have more familiarity than the drivers of the Zilla road and Upazilla road. On average, the truck, bus, microbus and car, auto rickshaw and motorcycle drivers had only 61–76% familiarity with traffic signs. The bus drivers had the highest level of understanding, followed by microbus and car drivers, truck drivers, motorcycle drivers and auto rickshaw drivers, respectively. The study results concluded that efforts are needed to train the drivers on the proper meanings and responses to traffic signs. These outcomes are believed to be essential for the Bangladesh Road Transport Authority and other relevant organizations.