The fan shroud assembly includes: a rectangular-shaped plenum having a first plenum portion of a larger side and a second plenum portion of a smaller side, which are mounted eccentrically; a fan shroud formed on an air discharge side of the plenum and having a airflow guide portion, in which a fan having a blade and a band for connecting the outer end of the blade, is positioned; and a motor for driving the fan, wherein a connection point between the first plenum portion and the airflow guide portion is located within a height (BH) of the band, and wherein a height (H1) from the bottom of the plenum to connection point between the first plenum portion and the airflow guide portion is higher than a height (H2) from the bottom of the plenum to connection point between the second plenum portion and the airflow guide portion satisfying H1H2.