Asia is a heterogeneous region with substantial variability in economic, social and palliative care development. While the global consumption of opioids has increased, the consumption in most Asian countries has not increased at the same rate. This is the first comprehensive study of opioid availability and accessibility for cancer patients in Asia. Data are reported on the availability and accessibility of opioids for the management of cancer pain in 20 of 28 countries. The countries in the report represent 2515 million of the region's 2612 million people (96%). With the exception of Japan and South Korea, opioid availability continues to be low throughout most of Asia. Formulary deficiencies are severe in several countries, in particular Bangladesh, Myanmar, Afghanistan, Kazakhstan and Laos. Even when opioids are on formulary, they are often unavailable, particularly in the same countries. Access is significantly impaired by widespread over-regulation that continues to be pervasive across the region.