In this research, we designed and implemented an advanced metal detector based on the Atmega328p microprocessor; it is used in the security field to prevent the entry of dangerous metal tools or explosives to places that require a high degree of safety such as schools, airports, universities and commercial malls. Where the mechanism of the electronic scheme of the detector was understood, including what it contains of active and passive electronic components, the microprocessor used how to program it and its technical specifications were identified. After that, we converted the electronic diagram into a printed circuit board (PCB) via easyada.com, And then print this circuit on special paper so that we can transfer it on the copper board, and a special solution was used to remove the copper residues from the board, after that holes were created and the electronic elements were soldered, Moving on to the software part, the Arduino Uno chip was used to act as an ISP programmer, through which the Atmaga328p controller was programmed using AVRDUDESS software, tested with a small coil with a diameter of 1.5cm. The detector gave excellent performance in detecting metal pieces such as copper, aluminum, iron and silver, as well as electrical wires in the walls, where the device screen shows the signal strength of the captured metal as well as the numerical symbol of the metal. It also discovered the presence of a sharp tool hidden in the mouth, shoes or inside the clothes, and the device achieved high performance In discovering metal parts and determining their properties, with an accuracy of 80%.