Joshi, who is at present director general of the elite National Security Guard, will lead the 1.8 lakh strong BSF as the post had fallen vacant on December 1 due to retirement of U K Bansal.
A 1976 batch IPS officer from Uttrakhand cadre, Joshi is due to retire in February 2014. He has also served in the Central Reserve Police Force as special director general of police.
In another appointment cleared by the appointments committee of the Cabinet headed by Prime Minister Manmohan Singh, Chadha, special secretary (internal security), has been appointed as director general of ITBP.
A 1977 batch IPS officer of AGMU cadre, Chadha will have a tenure till August next year. The post had fallen vacant after Ranjit Sinha was appointed as director of CBI.
Special Director General of BSF Arvind Ranjan has been appointed as director general, NSG.
Ranjan is a 1977 batch IPS officer of Kerala and has service till April 2015.
All the appointments will be effective from the dates these officers assume charge of their posts and till their superannuation or until further orders, whichever event takes place earlier, an official order said.