Gravitino is a very weakly interacting particle, that is suitable as dark matter particle candidate in supergravity theories. Because of its very small coupling, gravitino is very difficult to detect. The phenomenology of this scenario depends on the next lightest supersymmetric particle (NLSP) which is metastable with typical lifetime greater than one second. There are various possibilities for the NLSP and it turns out that each has distinct signatures that I will discuss in this talk.