Sub-county schools in Kenya form the lowest cadre of secondary schools.
They come after national, extra county and county schools respectively.
Kenyan learners who attain low marks in the KCPE national exam are admitted to these schools.
Majority of sub-county schools are mixed.
Most of them are day schools though a few are day/boarding schools.
They are available across all the 47 counties.
Here is a list of sub-county secondary schools in Garissa County:
| KNEC CODE AND NAME | TYPE | CATEGORY | |
| 1 | 45801105 UMUSALAMA GIRLS’ SECONDARY SCHOOL | Girls | Sub County |
| 2 | 45801109 BOYS TOWN SECONDARY | Boys | Sub County |
| 3 | 45801110 IFTIN GIRLS SECONDARY SCHOOL | Girls | Sub County |
| 4 | 45801111 TETU SECONDARY SCHOOL | Mixed | Sub County |
| 5 | 45801127 YATHRIB GIRLS SECONDARY SCHOOL | Girls | Sub County |
| 6 | 45801128 AL-RAWDAH HIGH SCHOOL | Mixed | Sub County |
| 7 | 45801132 WORLDVIEW HIGH SCHOOL | Mixed | Sub County |
| 8 | 45804103 COUNTY COUNCIL MIXED SECONDARY SCHOOL | Mixed | Sub County |
| 9 | 45804201 IJARA SECONDARY SCHOOL | Mixed | Sub County |
| 10 | 45805103 SHANTABAQ SECONDARY SCHOOL | Boys | Sub County |
| 11 | 45806301 GALMAGALA MIXED BOARDING SECONDARY SCHOOL | Mixed | Sub County |
| 12 | 45815108 HAJI IDRIS GIRLS SECONDARY SCHOOL | Girls | Sub County |
