The invention discloses a connection triangle measurement device and a measurement method. The measurement device is characterized by at least comprising two steel wires hung in silos, upper total stations located on the edges of silo openings, and lower total stations located under the silos, wherein at least two 360-degree prisms are mounted on each steel wire; at least one 360-degree prism is located above each silo opening, namely an upper 360-degree prism; at least one 360-degree prism is located below each silo opening, namely a lower 360-degree prism; the upper ends of the steel wires are fixed on brackets; counter weights immersed into damping liquids in oil drums are fixedly arranged at the lower ends of the steel wires; the 360-degree prisms located above the silo openings and the total stations on the silos are in the same height; the 360-degree prisms located below the silo openings and the total stations under the silos are in the same height; the upper total stations observe angles and distances from near silo points to the upper 360-degree prisms; and the lower total stations measure coordinates of the lower 360-degree prisms. The measurement method has the characteristics of high automation degree, high measurement speed and high observation accuracy.