This master's thesis presents the design of an accessible children playground using lightweight architecture for both children with disabilities and able-bodied children. The aim is to design an accessible children playground using pneumatic principles and materials. The 'pneumatic' principles and technology is one of the best options to design such kind of playground for children if necessary safety measures are taken into account. Use of textile fabrics rich in variety of colours as basic construction material also has an advantage in designing this pneumatic playground to impress and attract children very much. For that reason, by applying pneumatic principles, the accessible children playground has been designed which provides not only joyfulness and adventurous activities but also a good place to exercise while playing for both children with and without disabilities safely. Furthermore, it also provides interaction between normal children and disabled children so that they can assist each other, learn each other's abilities and improve physical developments, socializing and problem solving skills at a very young age. The first approach to this master's thesis is to study about types and treatments of physical disabilities to gain good knowledge about disabilities and what types of physical movements provide the best benefits for them. Thus, this knowledge has been incorporated in designing the present pneumatic accessible children playground. Then, discussion about pneumatic principles, technology, their basic structural forms and applications are studied. Finally, the design of the pneumatic accessible children playground with essential play equipment for the benefits of disabled children and able-bodied children has been presented in this thesis.