State Congress chief Bharatsinh Solanki said the party was collecting information about similar provisions in other states to prepare the draft bill.
The Assembly session will start from February 22.
The announcement comes against the backdrop of violent agitation of the Patel community seeking reservations under OBC quota.
"Congress is going to table a bill demanding 20 per cent reservation for those who are economically weaker and not covered under the current 49 per cent reservations," Solanki said at a press conference in Gandhinagar.
The quota agitation and the Patel community's resentment about BJP government seemingly helped Congress in the panchayat polls held in November. Before the elections Congress had supported Patel community's demand for reservation.