The value of a Quality-Adjusted Life Year (QALY) used to screen medicines for inclusion in the National List of Essential Medicines (NLEM) in 2013 was 160,000 baht per QALY. Any medicines that cost less than this amount is considered to be cost-effective. However, is this figure consistent with public opinion? What is the actual value for the Thai population? Research has shown that the value of a QALY for Thai people is consistent with the figures found in the study, i.e. between 113,000 baht and 325,000 baht. This can be divided into two scenarios. If treatment increases the quality of life but does not increase the lifespan of the patient, one QALY will be similar to the currently used value. However, if treatment increases the lifespan of a terminally-ill patient but does not increase the quality of life, the value of one QALY will be higher than 160,000 baht per QALY. Since research has shown that the value of one QALY is not the same depending on the scenario, the value used should also vary by considering the suitability for each situation.