Solar vacuum tube

The invention discloses a solar vacuum tube. The internal pipe wall of the vacuum tube is coated with a selective absorbing coating; at least one fin is placed horizontally/vertically in the vacuum tube; a U-shaped tube which is filled with an intermediate heat transfer medium passes through the fin and is arranged in the vacuum tube; and the fin is fixed on the U-shaped tube by a thermal contraction process. The solar vacuum tube provided by the invention improves the efficiency of photothermal conversion and reduces the cost of the system.