The invention relates to the technical field of drilling engineering, in particular to a variable amplitude cycloid borehole trajectory design method of a two-dimensional shallow horizontal well. The two-dimensional shallow horizontal well borehole trajectory design method includes the following steps: (1) determining a borehole trajectory basic design parameter; (2), determining a borehole trajectory form according to the acquired borehole trajectory basic design parameter of the step (1), acquiring the vertical depth H of a deflecting point and the borehole deflecting rate Z of a deflecting section if it is assumed that a single arc borehole trajectory is adopted, successively determining that the vertical depth H of the deflecting point is in a stable stratum and the borehole deflecting rate Z of the deflecting section satisfies the maximum deflecting ability of a deflecting tool, and adopting the single arc borehole trajectory design; and (3) otherwise, adopting a variable amplitude cycloid trajectory design, adopting an arc- cycloid trajectory design, i.e., a vertical shaft section-pre-inclined section-variable amplitude cycloid section-horizontal section trajectory design. The two-dimensional shallow horizontal well borehole trajectory design method only needs the basic parameter of a geological design, and is simple and convenient in computing process.