The Association of the Ship for Southeast Asian Youth of Thailand was born out of several unofficial alumni gatherings of the Ship for Southeast Asian Youth Program's (SSEAYP) past participants from 1974 and 1975. With all the rich experiences and strong friendships that have been cultivated between the program's participants , these alumni decided to form an association. The association's mission was to disseminated and inform the public on all the benefits the program has and will provide.

The loosely-formed association gradually grew and strengthened when a third group of Thai participants came back at the end of 1976. They formed a more official association consisting of participants from the first three years of program. At the Prince Hotel on New Petchaburi road, nine members (three from each participating year) formed a management committee. They provided the main thrust for the association over the coming years. From this committee , the official ASSEAY organization was formally registered as an independent entity on July 12, 1982 , ASSEAY , though a private and independent entity , has full support of the government's National Youth Bureau which is under the Office of the Prime Minister.

Despite starting out as a small group of alumni at the National Youth Bureau office , ASSEAY aims to eventually develop into a center of Ex-SSEAYPs in promoting the good understanding and supporting provide services and information as well as coordinate youth activities for youth groups and National Youth Bureau. (NYB - aka the OPP in nowadays.)

The Ship Nippon Maru on the letter "A" (represented the Alumni Association) with the color of Thai national flag. (There are three main colors in the Thai national flag ; red means Nation , white means religion - Buddhism , and  blue means His Majesty the King and the Chakri dynasty.)