Foreign investors can lease state land for commercial, industrial use for up to 50 years, similarly to citizens and citizen-owned companies. Foreign investors are not allowed however to lease residential state land, whereas citizens can lease them for up to 99 years. 
"2. Interpretation
In this Act, unless the context otherwise requires-
"state land" means unalienated state land and reacquired state land and includes any land outside Botswana ownership whereof is vested in the Republic;
"unalienated state land" means any land in Botswana other than- 
(a) land included in any tribal territory or the Barolong Farms other than land within a township established under the Townships Act;
(b) land included in any grant thereof made by or on behalf of Her Majesty prior to the commencement of this Act or on behalf of the President under this Act;
(c) the farms "Ramatlabama's Kuil" (60-JO), "Forest Hill" (9-KO), "Traquair" (10-KO) and "Crocodile Pools" (15-KO);
"reacquired state land" means any land in Botswana not being unalienated state land, ownership whereof is vested in the Republic.
3. Disposal of state land
The President may make and execute grants or other dispositions of any state land or of any interest therein.[...]" (State Land Act (Chapter 32:01) of 1980, as amended)
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"b) State Land
[...]
13. Allocation is made through Fixed Period State Grant of 99 years in the case of residential and 50 years for business and civic and community uses. However, only citizens are eligible for allocation of residential land. Licenses of up to 5 years and leases of up to 25 years are also granted. Grants below 10 years are not registrable at the Deeds Registry. [...]" (BOTSWANA LAND POLICY, GOVERNMENT PAPER NO. 4 OF 2015)

State Land Act (Chapter 32:01) of 1980, as amended
BOTSWANA LAND POLICY, GOVERNMENT PAPER NO. 4 OF 2015
[<a href="http://extwprlegs1.fao.org/docs/pdf/bot39081.pdf">Act</a>],[<a href="http://extwprlegs1.fao.org/docs/pdf/bot196817.pdf">Policy</a>]