In the year 2018 (2561), Wesak Day falls on 29 May 2018 (29 พฤษภาคม 2561)
You may also read on the Self Practice During Wesak (Visakha) Day.
The Visakha Puja or the Full Moon Day of the sixth lunar month is considered the most important the reason being that three unique events concerning the Buddha occurred on such Full Moon day of that month. Firstly, Queen Maha Maya gave birth to a son, Prince Siddhattha on the Full Moon Day of the lunar month of May. Secondly, thirty five years later the Prince, on the Full Moon Day of May became the Buddha, the Awakened One. Thirdly, forty five years later on the Full Moon Day of May, the Englightened One passed away.
His teaching, doctrine and discipline have attained universal recognition and have become memorials to him. As Buddhists know, the personal name of Lord Buddha was Siddhatta Gotama, and taht he was the only son of King Suddhodana and Queen Maha Maya of the Sakyan. The Prince was born under a banyan tree in the Lumbini Grove located between the two cities of Kapilavatthu and Devadaha. Seven days after his birth, his mother passed away and so he was nurtured by his foster mother, Maha Pajapati Gotami who was the youngest sister of his father.
At the age of sixteen the Prince married the beautiful Princess Yasodhara, the daughter of King Suppabuddha of the Kolyan. Thirteen years of luxurious married life gave the Prince adequate experience in realisation of the insubstantiality of worldly life. At twenty nine, not long after his wife Yasodhara had given birth to a son, Rahula, the Prince decided to renounce wordly life for a homeless one devoting himself to a disciplined quest for spiritual satisfaction. He spoke to his disciples about the two possible goals to which men devote their lives, that is, the noble or holy quest as described in the Ariyapariyesana Sutta, and the ignoble or unholy quest. Due to the delusion of self man is subject to Dukkha (suffering or a sense of unsatisfactoriness) which is clearly evident in the process of decay and death. The ignoble quest, to which many devote their lives, consists in seeking after things or states which are really unsatisfactory due to their inherent state of flux or change, the very conditions from which deliverance is needed.