This thesis aims to study and analyze about representation and construction of reality of nature in Thai fantasy novels. These 22 novels are written by four people such as: Jintawee wiwat, Tri Apirum, Pongsakorn and Moke-mung mueang. Four main concepts which is used in this thesis are: Ecocriticism, ecofeminism, representation, construction of reality. The result are: 1) There are two separate parts in image part which represents to nature are bad part and good part. For bad part is presented by non-human (animal, monster, god and plant) and setting (space and phenomenon of nature and phenomenon). Good part is also presented by non-human (animal, monster, god and plant) and setting (space and phenomenon of nature and phenomenon) too and show us about the beauty of nature. For the part of construction reality of nature it has five issues such as: language, curse word, creative nature, natural space, and ecotopia. To sum up, the representation and construction of reality of nature in Thai fantasy novels lead to a various system of reality by show us two separate ways are nature is more power than human and human is more power than nature or human can dominate nature. Anyways, the power of human and the power of nature are not completely victorious. Although, nature has power to dictate human life but human can still overcome the nature. However, Thai fantasy novels are demonstrated the ways of human action to nature by using the representation of nature. On the other hand, Humans are ready to overcome nature when humans know that nature is not a beautiful thing and threaten them. If nature is a beautiful thing and it has a lot of benefits to the humans, Humans could love and determinate to protect nature and in order to maintain the definition of goodness of human’s life.