The utility model provides a backpack, backpack includes: check are placed for notebook computer to first intermediate layer, the second intermediate layer, with the range upon range of setting of first intermediate layer, the second intermediate layer includes that the power places check, host computer and place check and current transformer and place check, the host computer is placed check and current transformer and is placed check and all be located the power and place the check top. Use the technical scheme of the utility model, backpack has notebook computer and places that check are placed to check, power, check are placed to the host computer and check are placed to the power mutual -inductor, when operating personnel transportation check out test set, can place corresponding equipment in backpack, and operating personnel passes through the multiple check out test set of backpack transportation, can solve the problem that can not transport the check out test set of among prior art existence effective, conveniently.