Vilasrao Deshmukh, a two-time chief minister of Maharashtra, died in 2012 due to multi-organ failure. Riteish is one of his three sons.
The actor took to micro-blogging website Twitter, and posted: "Happy Birthday PAPPA : the father that you were to me, is what I aspire to be to my son. 70thBirthAnniversasry," the 37-year-old tweeted.
Riteish, who is married to Genelia D'Souza, was blessed with a son in November 2014.