The company " Elektroistok " was founded in 1958 on the St .Vitus day. Its main activity was determined by  a decision of constitution apprioved by the Executive Council of the People's Republic of Serbia, which said:  “Transfer of power through the transmission grid system is defined in terms of Article 26 on the electric power  industry , on the entire territory of the People's Republic of Serbia . Activity of " Elektroistok "expanded in late  in 1958 towards designing and constructing  of power facilities , therefore the year 1958 is considered as the beginning of " “Elektroistok -Projektni biro”  Ltd. company foundation.


Intensive economic development , which we entered after the Second World War , following the period o  war-torn country reconstruction, influenced the rapid growth of electricity consumption in industry and the  households, and imposed the need for intensive building of electricity generation sources , and also the need for  the formation of the modern power system . 


The transfer was created and developed as an integral part of the system, important for overcoming the distance  to consumers and interconnecting power plants. In its initial function, the system power- consumer was first  established in Serbia 106 years ago, precisely in 1902 between HE Vučje and the city of Leskovac, eight years  after the first in Yugoslavia , and 11 years after realization of the world's first transmission of electricity. The  origins of the broader functions of electricity transmission are related to the year 1953, when the power system in  Serbia was conceived. Then, after a long period of planned construction, especially in the period of 1950 – 1953,  the lines and substations connecting the 110 kV voltage were developed and molded into the first network for the  transmission of electricity

For faster and more efficient development of the electric power system, 1957 the Law on electric power  industry organizations was passed, and in 1958 the appropriate organizational changes were completed in the  old production- transmission and distribution organizations. According to decision of Community of power  companies of Serbia and National Executive Council of the Republic of Serbia on 28 June 1958, " Elektroistok "  was established, as a special power utility for electricity transmission in the transmission network . Thus  transmission network became a single body of integrated power system in the united Serbian electric power  industry .It includes all transmission lines and substations of 110 kV and higher. 


Operational personnel , fixed and current assets ," Elektroistok " assumed by separating from the electric  power industry utilities in Serbia , which previously carried out the function of electricity transmission ,  including: TE Belgrade , mines and power plants Kostolac, Elektrovojvodina Novi Sad , HE Zvornik , Elektrokombinat Kraljevo , Kolubara , Electric company  Niš, electric company Zaječar , Electric company Leskovac and Elektrometohija Peć . At the time of its  establishment " Elektroistok " had seven engineers and 320 employees.


The first major change in the organization of " Elektroistok " were conducted during the period from  1960 to 1962 . Based on the established scale and dynamics of the transmission network, the access to the  implementation of the plan started. Four drive gears were formed: in Srbobran , Valjevo, Kruševac , as well  as design and construction plant in Belgrade and Niš , from which the units for the design and construction of  power facilities were separated later . Designing operations in " Elektroistok " - were created in 1960 in the "  Plant for the design and construction" design department . In 1973, together with the changes and transformation  of " Elektroistok " into business organization , came the separation of design and construction , and project  office was organized as a separate basic organizations of associated labor .


In the form OOUR Projektni biro was developing until the end of 1989, when, at the beginning of the year 1990,  project office was transformed into a department within PE " Elektroistok ." , until mid- 2005 when the Board  of Directors of PE " Elektroistok " at the meeting on 27 of May 2005, with the approval of the Government of  the Republic of Serbia ( Belgrade meeting on 23.06.2005 , the approval 023-3895/2005 ) made a decision on the  foundation of : 

Business company for the design, consulting and engineering of power and telecommunication facilities and  systems “Elektroistok -Projektni biro” Ltd. Belgrade ,based in Belgrade , Rovinjska no. 14 , which started  working on 1.07.2005 .