The behavior of startled desert mule deer (Odocoileus hemionus eremicus) has been described, but distances moved after being startled have not been reported. We located 8 radio-collared deer (6 females, 2 males) for 8 mo, intentionally approaching them afoot until we startled them, waited 15 min, and relocated them (≤90 min). The deer were startled and relocated 56 times. Mean time elapsed between startling and relocation was 34.5 min (SE = 3.9 min). Mean distance moved was 893.2 m. When researchers disturb mule deer before obtaining data describing movement or habitat use, they should abandon their attempts for 24 h to avoid bias in those data.