The invention discloses a fitting structure of a bevel flitch plate and a skirting line. The fitting structure comprises a horizontal flitch plate and a vertical flitch plate, wherein the horizontal flitch plate is connected with the vertical flitch plate through the skirting line; a first connecting trough is formed in the horizontal flitch plate; a second connecting trough is formed in the vertical flitch plate; two side edges of the skirting line are respectively clamped into the first connecting trough and the second connecting trough; the space between the inner-side surface of a clamped part of the skirting line and the inner side walls of the first connecting trough and the second connecting trough forms an epoxy glue sealing trough; the surface on the outer side of the clamped part of the skirting line is adhered to the outer side walls of the first connecting trough and the second connecting trough; an accommodation cavity is formed among the inner side wall of the skirting line, the end part of the horizontal flitch plate and the end part of the vertical flitch plate. The fitting structure has the advantages that the mounting firmness of the skirting line is effectively increased, impact caused in different angles when people go upstairs can be effectively resisted, and thus the service life of the skirting line can be prolonged.