What actors and actresses appeared in Psyko Metro - 2011?

You're likely referring to the Korean drama "Psycho But It's Okay" (also known as "It's Okay to Not Be Okay"). It aired in 2020, not 2011.

The main actors and actresses in "Psycho But It's Okay" are:

* Kim Soo-hyun as Moon Gang-tae

* Seo Ye-ji as Ko Moon-yeong

* Oh Jung-se as Moon Sang-tae

* Park Gyu-young as Nam Ju-ri

There are also several supporting actors and actresses. You can find a complete cast list on websites like MyDramaList or IMDb.