Abstract: Abstract: Aiming at low efficiency and low bolting rate, garlic bolt positioning laboriously and time-consuming in bolting process by the traditional garlic bolting device, a kind of garlic bolting device with hook was designed by measuring the stem diameter. The comparative experiments were carried out to investigate the effects of traditional bolting device and bolting device with hook on bolting force, garlic bolt and garlic yield under different time and rainfall conditions. Eight treatments were conducted, in which 2 bolting devices were provided for 4 weather conditions of early morning, morning and afternoon as well as rainfall condition. The traditional garlic bolting device consisted of a handle, a metal rod and a metal nail, and the angle between the metal nail and the metal rod was 90(. The bolting device with hook consisted of 4 parts: handle, metal rod, positioning design and metal hook, with the angle between metal rod and positioning design ranging from 135° to 180°, and the plane formed by the metal rod and positioning design was perpendicular to the plane formed by the positioning design and the sharp metal hook. Garlic bolt was broken by metal nail of the traditional garlic bolting device, through the observing the position of the metal nails to the middle of the garlic stem while pinching the handle with one hand and bolting the garlic bolt with the other hand. While the garlic bolt was broken by the metal hook by placing the metal hook to the middle of the garlic stem using positioning device and hook with one hand, and bolting the bolt with the other hand. The bolt hole pierced by nailwas smaller and much easilyblockedleading the bolting force too large using traditional bolting device, while the hole was larger and not easily blocked, so that the internal and external pressure of the garlic stem was always consistent using bolting device with hook. The hole was done by Lever action using traditional bolting device, while the hole was done directly through bolting force bolting device with hook. By testing various indices and statistical analysis for 8 treatments, the results indicated that the bolting force could be reduced, the stability and bolting efficiency improved using the bolting device with hook, while the garlic yield was not decreased. The best bolting period were in early morning , morning and rainfall weather conditions. The garlic bolt length, the highest bolting rate and the garlic bolt yield could significantly improved under the rainfall condition especially, reaching 47.7 cm, 99.7%, and 5 222.22 kg/hm2 respectively. In a comprehensive way, the best scheme for garlic bolting were in early morning, morning and rainfall conditions using hook bolting method. The conclusion could provide a reference for time and mechanization of bolting.