Abstract: To study the fruit vibration and bruise in their truck transport, by simulative three-degree-of-freedom vibration test, the vibrating acceleration transmissibility of plastic boxes packaging pears in every direction was studied; the effects of vibration frequency on pear bruise were analyzed; the relationship between vibrating times and vibrating accumulated acceleration were discussed when pears lost their marketability at a certain vibration frequency. The results showed: at a certain vibration frequency, the upper plastic boxes have, bigger transmissibility of vibration acceleration in every direction; vibration acceleration transmissibilities of top level plastic boxes in right-and-left direction and in front-and-back direction were far larger than that in up-and-down direction; under the same acceleration, the smaller the vibration frequency was, the more easily pear bruised. There was a certain relationship between vibration times N and its accumulated acceleration g₀ as pears lost their marketability at a definite frequency.