The average custodian salary at Duncan Hs was $19,769 , which is 25 percent lower than the average salary for this job in Oklahoma, and 72 percent lower than the national average for this job . Custodian salaries at Duncan Hs typically range from $12,091 to $29,848 (25th to 75th percentile). The highest reported custodian salary was $29,848. There are 5 employees at Duncan Hs with the job title custodian.