The invention relates to a manual hole digging pile high polymer grouting protection structure and a construction method thereof. The manual hole digging pile high polymer grouting protection structure is characterized in that a pile hole wall is set to be a waterproof supporting ring formed by high polymer grouting; a pressure grouting ring is arranged on the top of the waterproof supporting ring, and strengthening columns formed through high polymer grouting are distributed on the periphery of the waterproof supporting ring; in a bottom overbreak section of a pile hole, a lime strengthening layer is formed through lime pavement, and graded broken stones are laid on the lime strengthening layer to form a broken stone waterproof layer; and pressure grouting plates are fixedly arranged on the top face of the broken stone waterproof layer, a high polymer grouting solution is injected through bottom grouting holes formed in the pressure grouting plates and seeps into gaps of the graded broken stones, and a waterproof bottom plate is formed through expansion curing. The waterproofing and wall protecting work during construction is carried out in advance, bottom and side wall waterproofing and periphery supporting strengthening are combined, the technology is simple, and the project cost is low. The hole digging pile underground work conditions are improved, the later pile construction quality and progress are guaranteed, and obvious economic benefits and high popularization value are achieved.