Highest salary at Johnson County in year 2021 was $123,639. Number of employees at Johnson County in year 2021 was 73. Average annual salary was $31,416 and median salary was $31,044. Johnson County average salary is 33 percent lower than USA average and median salary is 29 percent lower than USA median salary. From 2020 to 2021, the average salary of employees at this employer increased 2.1 percent, the median salary increased 0.7 percent.