Abstract Public Accounts Committee (PAC) in the legislature is expected to be at the center of accountability in the budgetary process as it examines among others queries on annual audited accounts, the accounts and reports of Ministries, Departments and Agencies of the government, statutory corporations, boards, etc. as may, from time to time, be referred to it by the legislature or the executive. Above all, it enjoys the power to examine the causes which led or might have led to any excesses over approved appropriations. These conferred on it the special role of the reference point for other legislative House Committees in ensuring accountability in the polity. Despite these enormous responsibilities of the committee, the budgetary process in Nigeria continue to suffer sets backs over the years with attendant consequences. Using content analysis method of inquiry and drawing lessons from South Sudan, the paper examined the Nigerian experience and result shows that there is weak ex-ante scrutiny of the budgetary process by the committee in Nigeria as consultation at the preparation stages of the budgetary process is frail. The paper recommends for the legislature to exploit the role of Public Accounts Committee at the preparation’s stages of the budgetary process towards effective accountability and ensure the amendment of the standing powers of the Senate and House rules, and State Houses of Assembly to clearly mandate ex-ante powers for these committes in the budgetary process in Nigeria. Keywords: Public Accounts Committee, Legislature, Accountability, Budgetary Process.