Cash register devices are used in every place and every shopping area in the world. Cashier takes the money from customer and put the cash register. The structure of these devices does not have any control mechanisms. If the cashier does not use any money control device, counterfeit money may deposit into the account of companies working honestly. Especially, there may be many customers in the big shopping malls and sometimes they can constitute large queues in front of the cashier. In such cases, cashier may not pay much attention to whether the money is the fake or not. In this study, a new counterfeit money detection system, which is applicable on all the cash register devices, was designed. System is based on recognition of the appearing characters above money which is illuminated with ultraviolet light. Designed detection system can be applied on the money holding mechanisms which is over the small departments in cash register drawer. In the case of any fake money detection event, system can produce an alert with light, sound or using of short message service according to the selections. Designed new system aims to protect both cashier and companies against to ill-intentioned people. The most important features of the designed system are to be cost-effective and easily assembled in the every cash register.