County secondary schools in Kenya form the third tier after national and extra-county schools respectively.
Most of Kenyan learners are absorbed by these schools.
Admission to county schools is done online by the Ministry of Education.
They are either mixed or single-sex.
Here is a list of County Schools in Kirinyaga County:
| NAME | KNEC CODE | TYPE | CATEGORY | |
| 1 | ST. AGNES GIRLS SECONDARY SCHOOL – KIRANJA | 09203407 | Girls | County |
| 2 | KARIA SECONDARY SCHOOL | 09203408 | Boys | County |
| 3 | KAGUMO GIRLS SECONDARY SCHOOL | 09203409 | Girls | County |
| 4 | NJEGA BOYS SECONDARY SCHOOL | 09203427 | Boys | County |
| 5 | ST AGATHA KANYEKINE GIRLS’ SECONDARY SCHOOL | 09203431 | Girls | County |
| 6 | MUTIGE SECONDARY SCHOOL | 09222102 | Boys | County |
| 7 | ST. MARK’S GIRLS HIGH SCHOOL- THUMAITA | 09222205 | Girls | County |
| 8 | ST ANNS’ GITUBA GIRLS SECONDARY SCHOOL | 09222305 | Girls | County |
| 9 | KIAMUGUMO GIRLS’ SECONDARY SCHOOL | 09222306 | Girls | County |
| 10 | GATHAMBI GIRLS SECONDARY SCHOOL | 09223106 | Girls | County |
| 11 | KIBIRIGWI GIRLS SECONDARY SCHOOL | 09223201 | Girls | County |
| 12 | KIINE GIRLS’ SECONDARY SCHOOL | 09223202 | Girls | County |
| 13 | MUKANGU SECONDARY SCHOOL | 09223204 | Mixed | County |
| 14 | WANG’URU GIRLS’ SECONDARY SCHOOL | 09224104 | Girls | County |
| 15 | MURINDUKO SECONDARY SCHOOL | 09224203 | Mixed | County |
| 16 | ST. TRIZAS KUTUS GIRLS BOARDING SECONDARY SCHOOL | 09224204 | Girls | County |
| 17 | GAKUU MIXED DAY SECONDARY SCHOOL | 09224213 | Mixed | County |
| 18 | DR. BABLA KANG’ARU SECONDARY SCHOOL | 09239102 | Mixed | County |
| 19 | ST. MARY’S KAGIO BOYS HIGH SCHOOL | 09239106 | Boys | County |
| 20 | MWEA BOYS SECONDARY SCHOOL | 09239109 | Boys | County |