The present application relates to a tightness adjusting device for shoelaces, which includes a connection mechanism and a traction mechanism. The traction mechanism includes a traction assembly, the traction assembly includes a ring member hinged with the connection mechanism, the traction mechanism further includes an elastic adjusting assembly; the elastic adjusting assembly includes a connection block, a clamping block, an elastic member and a linkage member, a connection portion is connected to each end of the connection blocks, the connection portion is detachably connected to the ring member, the connection block divides the ring member into two shoelace holes, the clamping block is hinged with the connection block, the elastic member is configured to force the two clamping blocks away from each other, and to mount the shoelaces in the shoelace holes with the ring member, the clamping block is connected to the connection portion by the linkage member.