The County Assembly of Makueni is established under Article 176 (1) of the Constitution of Kenya to undertake the following roles:
- Vetting and approval of nominees for appointment to County public offices as may be provided for in the County Government Act or any other law
- Performing roles set out under Article 185 of the Constitution
- Approving the budget and expenditure of the County government in accordance with Article 207 of the Constitution, and the legislation contemplated in Article 220(2) of the Constitution, guided by Articles 201 and 203 of the Constitution
- Approving the borrowing by the County government in accordance with Article 212 of the Constitution
- Approving County Development Planning
- Performing such other role as may be set out under the Constitution or legislation.