A snare-adjusting device is mounted on a snare drum for adjusting tension of a snare and has a base, adjustment assembly and snare mount. The adjustment assembly is mounted through the base and has a barrel, shaft, slider, adjustment head and friction ring. The barrel has two ends. The shaft is mounted rotatably through the barrel. The slider is mounted slidably in and engages one end of the barrel and is mounted on the shaft using threads. The adjustment head is mounted securely on the shaft. The friction ring is mounted slidably through an other end of the barrel, is pressed by a resilient device to abut the adjustment head and provide friction against rotation of the adjustment head. The snare mount is attached to the slider and connects to the snare. The friction holds the adjustment head securely to maintain a steady timbre.