The invention relates to a rapid-to-install compact bus duct shell, belonging to the technical field of power transmission and distribution. The bus duct shell comprises an H-shaped section and a U-shaped section. A plurality of vertical tenons are arranged at the upper ends of the inner walls of the leg plates of the H-shaped section. A plurality of vertical guide grooves which are respectively and correspondingly matched with the vertical tenons one by one are arranged on the outer walls of the U-shaped section. Strip raised parts are arranged at the upper parts of the inner walls of the leg plates of the H-shaped section. Strip raised part anti-slipping teeth are arranged on the lower end surfaces of the two strip raised parts. Leg plate anti-slipping teeth are respectively arranged on the inner walls of the leg plates below the two strip raised parts. The opening of the U-shaped section is upward and U-shaped section top surface anti-slipping teeth are respectively arranged on the upper end surfaces of two opposite side plates. U-shaped section outer wall anti-slipping teeth are respectively arranged on the outer walls of the two opposite side plates of the U-shaped section. The U-shaped section is inserted into a space between the inner walls of the two leg plates from top to bottom. The U-shaped section top surface anti-slipping teeth are respectively engaged with the strip raised part anti-slipping teeth. The U-shaped section outer wall anti-slipping teeth are respectively engaged with the leg plate anti-slipping teeth. The rapid-to-install compact bus duct shell has the advantages that the bus duct shell is rapid and convenient to install and the sealing performance is good.