A photographing method for use in a device includes: monitoring a current time and determining whether the current time reaches a preset shooting time; taking a first picture of an object when it is determined that the current time reaches the preset shooting time; determining a difference between a first image in a preset area of the first picture and a second image in the preset area of a second picture taken at a previous preset shooting time, the preset area corresponding to the object; and saving the first picture if the determined difference is equal to or greater than a preset threshold value.