The invention relates to a skirtboard thread lock. The skirtboard thread lock is designed for solving the technical problems that existing similar products are in shortage of further gear ring meshinglocking structures, and the lock cylinder popup structure design is not good. The skirtboard thread lock is characterized in that an upper gear ring of an upper base port of a base is engaged with anouter gear ring at an upper shell port in one end of a lock shell sleeved with the base, and a lower shell port in the other end of the lock shell in the base abuts against an outer diameter ring ribof the lock cylinder through a spring; the lock cylinder in the lock shell is further provided with a shaft sleeve, the shaft sleeve, the lock cylinder, the lock shell and the base are sequentially arranged in a sleeved manner, a pin is used for sequentially penetrating the lock shell, the shaft sleeve and the lock cylinder to be connected into a whole, and pin holes of the lock shell and the shaft sleeve are kidney-shaped long holes. A ring groove is formed in the inner diameter of the lower shell port of the lock shell, the lock cylinder outer diameter flat key section corresponding to thering groove is provided with a flat key groove, and elastic bodies symmetrically arranged at the flat key groove position are steel wire springs or elastic piece springs. The shaft sleeve drives the elastic bodies to be contained in the shaft sleeve and the lock cylinder, the elastic bodies disengage from the ring groove of the lock shell, the lock shell pops up of the base under the action of thesprings, and accordingly, the inner gear ring of the base disengages from the outer gear ring of the lock shell.