Joint sitting of both Houses of Parliament is chaired by: 

The joint sitting of the Parliament is called by the President of India as per Article 108 of the Constitution of India- Art. 108. Joint sitting of both Houses in certain cases (1) If after a Bill has been passed by one House and transmitted to the other House (a) the Bill is rejected by the other House; or (b) the Houses have finally disagreed as to the amendments to be made in the Bill; or (c) more than six months elapse from the date of the reception of the Bill by the other House without the Bill being passed by it the President may, unless the Bill has lapsed by reason of a dissolution of the House of the People, notify to the Houses by message if they are sitting or by public notification if they are not sitting, his intention to summon them to meet in a joint sitting for the purpose of deliberating and voting on the Bill: Provided that nothing in this clause shall apply to a Money Bill The Joint sitting of Houses is presided over by the Speaker of the Lok Sabha or, in their absence, by the Deputy Speaker of the Lok Sabha, or in their absence, the Deputy Chairman of the Rajya Sabha.