Writer Roop Narayan Sonkar has alleged that Roshan stole the 'Krrish 3' story from his novel 'Suardan'.
Sonkar has submitted a copy of his novel along with the complaint, police said, adding a case has been registered against the celebrated filmmaker.
The novelist claimed he published 'Suardan' in 2010 in which he had envisioned a creature combining 'manav' (man) and 'janwar' (animal) and named it 'Manwar'.
He said the 2013 film also has a creature combining the attributes of man and animal and claimed Roshan used his story without obtaining his permission.
The police said the matter will be investigated and, if accusations are found to be true, further action will be taken.