As of January 2025, the International Society on MCDM has 2470 members from 105 countries. Top five memberships are from India, United States, Turkey, Brazil and Spain, accounting for 1029 of all members. There are five or fewer members from 52 countries. The color of each country on the map below varies in darkness depending on the number of members in that country. The exact membership sizes are given by Country in the table following the map.
| Country | Members |
| India | 415 |
| United States | 196 |
| Turkey | 168 |
| Brazil | 135 |
| Spain | 115 |
| Iran | 93 |
| China | 93 |
| United Kingdom | 80 |
| Canada | 68 |
| Italy | 67 |
| Germany | 66 |
| Portugal | 65 |
| France | 58 |
| Finland | 52 |
| Taiwan | 50 |
| Poland | 43 |
| Greece | 36 |
| Netherlands | 34 |
| Colombia | 32 |
| Malaysia | 32 |
| Indonesia | 31 |
| Russia | 27 |
| Nigeria | 26 |
| Belgium | 26 |
| Mexico | 25 |
| Australia | 24 |
| Algeria | 24 |
| Sweden | 18 |
| South Korea | 17 |
| Tunisia | 17 |
| Denmark | 15 |
| Switzerland | 14 |
| Austria | 13 |
| Czech Republic | 13 |
| Serbia | 13 |
| Romania | 12 |
| Saudi Arabia | 12 |
| Thailand | 12 |
| Egypt | 11 |
| New Zealand | 11 |
| Japan | 10 |
| Pakistan | 10 |
| South Africa | 10 |
| Chile | 9 |
| Hungary | 9 |
| Morocco | 9 |
| Hong Kong S.A.R., China | 9 |
| Nepal | 8 |
| Argentina | 7 |
| Ireland | 7 |
| Israel | 7 |
| Cuba | 6 |
| Bangladesh | 6 |
| Belarus | 5 |
| Bulgaria | 5 |
| Croatia | 5 |
| Lithuania | 5 |
| United Arab Emirates | 5 |
| Oman | 5 |
| Norway | 4 |
| Ukraine | 4 |
| Georgia | 3 |
| Latvia | 3 |
| Libya | 3 |
| Philippines | 3 |
| Slovenia | 3 |
| Ethiopia | 3 |
| Bahrain | 2 |
| Ghana | 2 |
| Iraq | 2 |
| Jordan | 2 |
| Kenya | 2 |
| Kuwait | 2 |
| Peru | 2 |
| Singapore | 2 |
| Sudan | 2 |
| Vietnam | 2 |
| Afghanistan | 1 |
| Armenia | 1 |
| Bahamas | 1 |
| Benin | 1 |
| Bosnia and Herzegovina | 1 |
| Ecuador | 1 |
| Estonia | 1 |
| Guatemala | 1 |
| Iceland | 1 |
| Kazakhstan | 1 |
| Luxembourg | 1 |
| Macedonia | 1 |
| Mauritius | 1 |
| Mongolia | 1 |
| Montenegro | 1 |
| Myanmar | 1 |
| Namibia | 1 |
| Palestinian Territory | 1 |
| Panama | 1 |
| Papua New Guinea | 1 |
| Qatar | 1 |
| Senegal | 1 |
| Sierra Leone | 1 |
| Slovakia | 1 |
| Sri Lanka | 1 |
| Tanzania | 1 |
| Venezuela | 1 |
| Vietnam | 1 |
| TOTAL | 2470 |