Highest salary at O'brien County in year 2022 was $135,860. Number of employees at O'brien County in year 2022 was 137. Average annual salary was $40,886 and median salary was $53,045. O'brien County average salary is 13 percent lower than USA average and median salary is 22 percent higher than USA median salary. From 2021 to 2022, the median salary increased 0.3 percent.