The invention discloses a simple micro optical fiber attenuation method. The method includes the following steps that: a cylinder with circular blocking plates is provided; a 2 cm V-shaped opening is formed in the circular blocking plates at the two ends of the cylinder respectively, and the diameter of the circular blocking plates is 6 cm, and the upper end at the width direction of each V-shaped opening is slightly larger than the diameter of a commonly-used micro optical fiber, and the lower end of the V-shaped opening is slightly smaller than the diameter of the commonly-used micro optical fiber, and the V-shaped openings are used for fixing the entering end and outgoing end of the micro optical fiber; the jumper of the micro optical fiber is wound for a certain number of loops according to a calculated light beam signal attenuation value of each loop, so that light beam signals can be attenuated to an appropriate DB level, and therefore, a simple micro optical fiber manual attenuator can be fabricated; the number of wound loops can be adjusted through the simple micro optical fiber manual attenuator, so that light beam signals can be attenuated by a certain numerical value, and therefore, equipment, instruments and devices can work normally, and can complete tasks in construction fast, simply and easily.