The bandh has been called by the umbrella organisation of Kannada and farmers' outfit 'Kannada Okkoota'.
Section 144 of Criminal Procedure Code has been imposed in Bengaluru Urban, Mandya, Mysuru, Chamarajanagara, Ramanagara and Hassan districts.
22 incoming and outgoing flights in the state have been cancelled.
Police have detained 50 pro-Kannada organisations' members to maintain the law and order, NDTV reported.
The bandh, which started at 6 am, will end at 6 in the evening.