The invention relates to a connecting structure of a main tower column and a foundation of a single-column stay wire tower. The connecting structure comprises a hemispherical embedded steel plate, an embedded bolt, a hemispherical bottom plate, a lattice type bottom column and four surrounding plates, wherein multiple hook-shaped reinforcing steel bars extending downwards are welded to the inner side of the hemispherical embedded steel plate, the bottom of the hemispherical embedded steel plate and the lower portions of the hook-shaped reinforcing steel bars are embedded in the concrete foundation, and a bolt hole is formed in the center of the top of the hemispherical embedded steel plate; multiple anchor bars are welded to the lower end of the embedded bolt, the lower portion of the embedded bolt is embedded in the concrete foundation, and the upper end of the embedded bolt penetrates out of the bolt hole of the top of the hemispherical embedded steel plate; the inner surface of the hemispherical bottom plate is attached to the outer surface of the hemispherical embedded steel plate; another bolt hole is formed in the center of the top of the hemispherical bottom plate and the upper end of the embedded bolt penetrates out of the bolt hole and is then fastened through two nuts; a reverse conical lattice type bottom column structure comprising four main materials is adopted in the lattice type bottom column; the four surrounding plates are welded through lateral sides, so that a square barrel structure is formed, the lower end of the lattice type bottom column is tightly sleeved with the square barrel structure, and the lower edges of the surrounding plates are attached and welded to the top face of the hemispherical bottom plate.