Yi peng Yi (Yee) = Two, Peng = Full Moon.Yi peng means the full moon night in the 2nd of the Thai Lanna Calendar. So exact date changes every year. Yi peng 2020 For this year will be celebrated on 31st October 2020 Small krathong and 1st November 2020 Big Krathong Parade in the city Yi peng (or Yee Peng) is celebrated when the local go to temple for listening to the monks pray of offering lantern to the monks. Locals decorated their house with hanging Khom loy or lantern. Light up the lantern for give praise to Lord Buddha.