These photographs show the four-time Ballon d'Or winner posing alongside the children - all kitted out in the new Barcelona shirt - as he joined goalkeeper Jose Manuel Pinto at the Unicef event.
The pair joined the group of Thai children and youths, with and without learning disabilities, as they tried their hand at shooting past Pinto and both players signed autographs for the young Barcelona supporters.
Say cheese: Lionel Messi poses with Thai children with learning diabilities at a Unicef event in BangkokThere was also an opportunity for the children to ask Barcelona's prize asset questions at the event to promote social inclusion for children with disabilities.
Barcelona are preparing for their friendly against the Thailand national team in Bangkok on Wednesday, and £50million signing Neymar was with his other team-mates at another public event.
The Brazil forward was joined by countryman Adriano and Chilean Alexis Sanchez as they talked to a group of young Thai footballers.
Hold still: Lionel Messi signs the shirt of one young supporter as others look on in awe
Q&A: Messi (left) answers questions from disabled children at the Okura hotel in Bangkok
Pitching in: Messi and Jose Manuel Pinto talk to the children while on Barcelona's eastern tour
Taking aim: Messi watched as the children took shots at goalkeeper Pinto
Strutting his stuff: Messi was in high spirits as he roles the ball to one of the youngsters
Happy days: Messi and Pinto pose for pictures with the boys, who donned Barcelona shirts
Warm welcome: Neymar (right) Adriano and Alexis Sanchez (left) give a traditional Thai greeting in Bangkok
Mixing it up: Neymar poses with some of his team-mates and a group of young Thai footballers
