The invention relates to a U-shaped glass installation mechanism which comprises an installation piece. U-shaped glass is arranged on the installation piece which is provided with installation grooves. The U-shaped glass is arranged in the installation grooves. The U-shaped glass installation mechanism further comprises a gap filling strip. The gap filling strip comprises a strip body. A gap is arranged between the adjacent installation grooves. The strip body stretches into the gap and is located between the two adjacent pieces of U-shaped glass. The U-shaped glass is installed through the installation grooves in the installation piece and the gap filling strip, the U-shaped glass can be reliably installed, influences of thermal expansion on the glass are effectively controlled, the fireproof and waterproof performance of the whole U-shaped glass is improved, and the U-shaped glass application range is wider. Meanwhile, the U-shaped glass installation mechanism is simplified, the construction difficulty is lowered, and curtain wall installation is more reliable and rapider.