The invention provides a method for supporting an aeolian sand tunnel entrance arch door frame type jet grouting pile and relates to the technical field of tunnel construction. The method comprises the steps of laying off jet grouting piles on the earth's surface of a hidden hole entrance, performing vertical jet grouting pile construction, and excavating an open cut tunnel and the hidden hole. The method has the advantages that the vertical jet grouting pile are snapped with each other, so that an arch door frame type continuous concrete structure is formed at the hidden hole entrance of a tunnel, stable side upward slopes and hidden hole advance support conditions are provided for tunnel hidden hole and open cut tunnel construction, large scale landside during construction is avoided, and it is guaranteed that the tunnel hidden hole construction is performed smoothly and safely. According to the technical scheme, the key problem of hidden hole entrance construction of the aeolian sand tunnel is solved; the method is very favorable for reducing project cost and project construction period, the method is wide in technical adaptive range, the structural stress is scientific, design parameters can be flexibly adjusted according to the tunnel entrance geological and geomorphological conditions, and the construction is convenient and safe.