Generally, a foreign investor may not own land, but may lease land for a period of up to 99 years, renewable.  However, in the case of agricultural and forestry  land, a foreign investor may only lease such lands for up to 30 and 60 years, respectively. These can be renewed upon mutual consent by the parties.
"Section 4. Interpretations
In this Act, unless the context otherwise requires the following words and expressions shall have the meanings assigned to them- [...]
"Foreign company" means a company as defined by the Southern Sudan Investment law. [...]
"Land" means all land-based natural resources, including urban land, rural land, forest land, pastureland, swampland, floodplains, flora, and local fishing grounds, and lands under which subterranean resources exist, but not those subterranean resources themselves.
[...]
CHAPTER II: LAND OWNERSHIP [...]
Section 7. Ownership and Tenure System
(1) All land in Southern Sudan is owned by the people of Southern Sudan and its usage shall be regulated by the Government. 
(2) Land may be acquired, held and transacted through the following tenure systems:-
a) Customary; b) Freehold; and c) Leasehold.
[...]
Section 9. Classification of Land: 
All land in Southern Sudan shall be classified as public, community or private land.
[...]
Section 12. Private Land
Private land includes:(1) any registered land held by any person under a freehold tenure; or (2) land held by any person under leasehold tenure; or (3) any other land that may be declared private land by law.
[...]
CHAPTER IV: RIGHTS TO LAND [...]
Section 14. Rights of Non-Citizens to Land
Subject to the provisions of section 16 of this Act, individual or collective foreign entities may acquire leasehold or other interest in Land for a specified period and not freehold in land in Southern Sudan, for residential or investment purposes or for any other reasons in conformity with the interest of the people of Southern Sudan and in accordance with the provisions of the Investment law or any other Law. 
[...]
CHAPTER VI DERIVATIVE RIGHTS TO LAND
Section 18. Lease 
(1) Any person owning land in Southern Sudan may lease this right to another person or persons for a fixed period of time in accordance with the provisions of this Act. 
(2) The contract of lease shall not be more than 99 years.
(3) Unless otherwise provided for in this Act or any other law, the provisions of subsection (1) above, shall apply to all leases including those governed by customary law and any other law. 
Section 19. Long Term Lease 
(1) A long term lease is a lease for more than one year and such a lease shall be in a written form. 
(2) A long term lease shall not exceed 99 years, and any lease for more than 99 years shall be considered a lease for 99 years with in the meaning of this section.[...]" (Land Act, 2009, Sections 7, 14 and 27)
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"Article 5. Definitions
In this Act, unless the context otherwise requires, the following words and expressions shall carry the meanings assigned to them — [...]
"domestic business organization" means a business organization that is owned by the national; [...]
"foreign direct investment" means an investment where the investor is not a national as defined in this Act and has majority shares, financing, managerial, administrative and technical personnel in an enterprise;
"foreign investor" means any natural or juridical person who is a resident or a citizen of a foreign county, any legal entity that was founded and registered under the law of a foreign country or was founded under the law applicable in Southern Sudan with a legal address or principal place of business in a foreign country; [...]
"national" mean any citizen of Southern Sudan or any company, partnership, association or body, whether corporate or non corporate in which the majority capital or financial interest is owned by citizens of Southern Sudan and includes a statutory corporation;
[...]
Second schedule. Benefits and incentives [...]
3. Access to Land for Investment
The Government of Southern Sudan and the Local Authorities shall provide land for investment in any of the priority areas mentioned in First Schedule. Notwithstanding any other provisions of the law, the following conditions shall be deemed included in the decisions on investment in the priority areas listed in the First Schedule:
a. general investments in agriculture - other than forestry and paper wood - shall not exceed 30 years for a foreign investor subject to renewal by mutual consent by the parties;
b. a foreign investor who wishes to invest in plantation forestry and depending on periods of harvest, shall not exceed 60 years subject to renewal by mutual consent by the parties;
c. quarrying shall not exceed the life of the quarry and, subject to renewal of license, renegotiate favorable terms with the ministry concerned; and
d. mining shall not exceed the lifespan of the mine, as defined in a concession agreement and subject to renewal of the license through favorable terms between the parties.[...]" (Investment Promotion Act, 2009, Second Schedule, Section 3)
Land Act of 2009, 
Investment Promotion Act, 2009, Second Schedule, Section 3
[<a href="https://mojca.gov.ss/wp-content/uploads/2023/03/Land-Act-2009.pdf">Act</a>],[<a href="https://mojca.gov.ss/wp-content/uploads/2023/03/Investment-Promotion-Act-2009.pdf ">Act</a>]