Two “remotely-piloted aircraft systems” (RPAS) go into service from Aberdeen and Inverness on Wednesday 1 May.
They could also be used in incidents such as road crashes, and to support “pre-planned operations and events”, the force said.
It said the drones would be able to search large areas faster than officers on the ground, especially in places hard to get to.
Police Scotland said they would be deployed by specially-trained officers from its operational support units and transported in marked police vehicles.
It said operations would be publicised via social media “where possible” so people knew one of the drones was operating nearby.
Head of specialist services Chief Superintendent Matt Richards said: “The addition of the RPAS to our air support capability will ensure we can deliver this service to the north of the country when previously weather or terrain may have prevented or delayed this.
“The introduction of the RPAS will be hugely beneficial to teams, for example, when searching for vulnerable or missing people, particularly in the remote areas that we have in the north of Scotland.
“The RPAS will not replace the Police Scotland helicopter and there will still be occasions where we deploy the helicopter in the north rather than the RPAS.
He said images recorded would be “managed in line with current guidelines and privacy laws including General Data Protection Regulations”.
Justice Secretary Humza Yousaf said: “This state-of-the-art new equipment will help Police Scotland keep communities safe, enhancing their search capabilities for vulnerable people, particularly over wide and challenging terrain.”
Scottish Police Authority chair Susan Deacon said: “This new system is a further step forward in ensuring Police Scotland has the tools and technology they need to keep people and communities safe.”
Chief Superintendent George MacDonald, Police Scotland’s Highlands and Islands divisional commander, said: “The introduction of the RPAS will be a huge benefit to policing and to the safety and well-being of our communities in the north of Scotland.
“The RPAS will be able to provide support in a variety of incidents and in particular will benefit search operations for missing or vulnerable people.”
Chief Superintendent Campbell Thomson, his north east counterpart, said: “Similar to the Highlands and Islands, we see a high number of missing person enquiries that cover large geographical areas so the RPAS will be of great benefit to officers as well as the additional support it will provide at other incidents such as serious road traffic collisions.”
A total of 3,494 people were reported missing in the north east last year and 2,343 in the Highlands and Islands.
Officers have also not ruled out their use in covert surveillance.
The force said it would fully comply with Civil Aviation Authority guidance on drone use, but has special permissions to “allow us to operate at a variety of incidents, both in rural and congested areas”.