The theft occurred on Saturday at the Holy Rosary Church on the 3200 block of Philadelphia Pike.
The church had placed money earned during its carnival event on Friday inside a safe.
When a carnival volunteer opened the safe late Saturday afternoon, he found that a large amount of the cash was missing.
Troopers found no signs of forced entry into the church or the safe.
Anyone with information in reference to this incident is asked to contact Delaware State Police at 302-761-6677 extension 328.