目的　探讨睡眠剥夺条件下服用咖啡因对工作绩效的影响。　方法　８ 名受试者用药前后自身对照，每名受试者重复５ 次实验。每次实验时在从６：００ 至次日９：００ 的２７ ｈ 的睡眠剥夺过程中于凌晨１：００ 分别服用安慰剂（食用淀粉）或咖啡因（ ２００ ｍ ｇ 和３００ ｍ ｇ）或苯丙胺（５ ｍ ｇ 和 １０ｍ ｇ），采用随机双盲给药。并在服药前１ ｈ 及服药后１ ｈ、３ ｈ、５ ｈ、７ ｈ 各完成一组认知任务工作绩效的测试。　结果　与安慰剂组比较，咖啡因可以显著降低单、双任务反应时、双任务跟踪误差（Ｐ＜０．０５）；服用咖啡因后主观任务难度降低（Ｐ＜ ０．０５） 。咖啡因 ２００ ｍ ｇ、３００ ｍ ｇ 的作用效果与苯丙胺５ ｍ ｇ、１０ ｍ ｇ 作用基本相当。咖啡因的这些作用在服药后１ ｈ 即可出现，持续至服药后７ ｈ。２００ ｍ ｇ 与３００ ｍ ｇ 咖啡因组间无显著差异（Ｐ＜ ０．０５）。　结论　咖啡因２００ ｍ ｇ 和咖啡因３００ ｍ ｇ 对于睡眠不足和睡眠剥夺引起的工作绩效的变化具有明显的改善作用 Objective To explore the effect of taking caffeine on work performance under sleep deprivation. Methods Eight subjects before and after treatment with their own control, each subject repeated 5 experiments. Placebo (dietary starch) or caffeine (200 and 300 mg) or amphetamines (200 mg and 300 mg respectively) were administered at 1:00 am during sleep deprivation from 6:00 am to 9:00 am the following day for each experiment (5 m g and 10 m g) were administered in a randomized double-blind manner. And a group of cognitive task performance tests were completed 1 h before taking medicine and 1 h, 3 h, 5 h, 7 h after taking medicine. Results Compared with the placebo group, caffeine significantly reduced the double-task tracking error (P <0.05) when single and dual tasks were responded to, while the subjective task difficulty was lower after taking caffeine (P <0.05). The effects of caffeine 200 m g and 300 m g are basically the same as that of amphetamine 5 m g and 10 m g. These effects of caffeine appear 1 h after taking the medication, continuing until 7 h after taking the medication. There was no significant difference between 200 m g and 300 m g caffeine groups (P <0.05). CONCLUSIONS: Caffeine 200 m g and caffeine 300 m g have significantly improved sleep performance and job performance due to sleep deprivation