The 51-year-old coach has already worked as Walter Zenga’s assistant in Al Nassr Riyadh and Al Nasr Dubai.
Cusin will assist Mojtaba Sarasiaei, who succeeded Yahya Golmohammadi in the Mashhad-based football team.
He started his coaching career in Italian team Arezzo and has also worked at Congo national football team, Fujairah and Al Ittihad Tripoli as head coach.
Shahr Khodro sits sixth in the Iran Professional League (IPL) with 29 points, five points behind leader Persepolis.