Chandra, a 1979-batch Indian Revenue Service officer, was till recently posted as the Principal Chief Commissioner of Income Tax in Ahmedabad and was heading the Gujarat region.
With his posting, the CBDT is in full strength now.
Officials said the appointment orders for Chandra were issued by the Finance Ministry recently and he took over the charge today.
His portfolio will soon be notified by the Ministry, sources said.
Earlier this month, another senior IRS officer, M C Mishra, had taken charge as a member in the Board after the government issued orders in this regard.
Apart from Chairman, the CBDT has six members and is the supreme body for framing policy and administrative issues related to direct taxes and the IT Department.