Thein Sein was to attend the World Economic Forum on East Asia, which will host Nobel laureate Suu Kyi as part of her historic first foray outside Myanmar in 24 years.
"Thailand and Myanmar decided to postpone the Myanmar president's official visit to Thailand to 4-5 June," Thai foreign ministry spokesman Thani Thongpakdi told AFP, adding that Suu Kyi "will still come as planned".
Officials at the Bangkok economic forum confirmed Suu Kyi's attendance -- including at two events on Friday -- and the cancellation by Thein Sein.