The invention relates to oxygen preparation equipment and method based on natural water sources. The oxygen preparation equipment comprises a water source collection device fixed outdoors, wherein an opening is formed in the water source collection device, the water source collection device is connected with a water outlet pipe, a water collection bottle is arranged below the water outlet pipe, the bottom of the water collection bottle is communicated with an oxygen preparation bottle, and reaction raw materials capable of reacting with water to generate oxygen are placed in the oxygen preparation bottle. According to the oxygen preparation equipment, the natural water sources such as dews, rainwater or snow water are collected by virtue of the water source collection device so as to prepare oxygen and are effectively utilized, so that the water sources are saved; the oxygen preparation equipment can be mounted outside a building or other places requiring oxygen, so that the oxygen content is increased; and meanwhile, collected fog water and rain water are limited, and the content of prepared oxygen is not too high, so that an oxygen poisoning phenomenon caused by an over-high oxygen concentration is avoided, and the content of oxygen in air is increased within a reasonable range.