Thieves stole cash from the Fishpond pub in Matlock Bath on Monday night.
Burglars broke into the South Parade pub between 11.30pm on Monday, April 11 and 10am on Tuesday, April 12.
They attacked a fruit machine and broke into the till and stole cash from both.
A police spokeswoman said: “We are not sure how they got in and we are investigating. We are appealing for any witnesses to come forward.”
Anyone with any information can contact police on 0345 123 33 33.