The Yerevan trolleybus system (Armenian: Երևանի տրոլեյբուսային համակարգեր) forms part of the public transport network in Yerevan, the capital city of Armenia. Since the closure of the Gyumri trolleybus system in 2005, it has been Armenia’s only trolleybus system.

Opened on 16 August 1949, the system was once much more extensive than it is today. At its greatest extent, the system had 20 lines, operated by a total of 300 trolleybuses, the vast majority of which were either Czech made Škoda 9Tr or 14Tr units, or Soviet made ZiU-682 models.

In recent years, the system has shrunk, and most of the Soviet era trolleybuses have been replaced by newer vehicles.

As of December 2024, the Yerevan trolleybus network consists of 5 routes:

Nr 1 Garegin Nzhdeh Square - Dzhrvezh;
Nr 2 City station of aeration - Nubarashen road;
Nr 9 Circus - Avan;
Nr 10 Nor Nork (Mikoyan street, 15) - Davtashen (4th block);
Nr 15 Erebuni airport - Block 15.

In July 2023, two new lines were introduced as new trolleybuses arrived to the fleet. Lines 2A and 10A were extended versions of lines 2 and 10, the lines continue without wires which was made possible with the new buses. In December 2024, routes 2A and 10A were closed, and routes 2 and 10 were extended.

The Yerevan trolleybus fleet mostly consists of new Chinese trolleybuses Yutong ZK6128BEVG (15 vehicles) and Zhongtong LCK6126E (15 vehicles). There are also more than 30 Russian-made trolleybuses LiAZ-5280 in the fleet. A significant number of Škoda 14Tr vehicles were replaced by 30 new Chinese trolleybuses in December 2024.

The second hand Berliet ER100 trolleybuses originally used on the Lyon trolleybus system ended in 2023.