The invention relates to a navel paste for treating night sweat, spontaneous sweating, enuresis, and lax and a preparation method thereof. The navel paste is prepared by the following raw materials according to parts by weight: 8-12 g of nutgall, 8-12 g of milk veteh, 1-2 g of cinnamon, and 1-2 g of costustoot. The preparation method of the navel paste comprises the steps that: the nutgall is ground; the volatile of the cinnamon and the costustoot is extracted; the milk veteh is extracted by decocting; finished products are compounded, and the like. The navel paste has the advantages of choice of drugs scouring, a medicine multi-purpose, executing astringing and supplementing, reasonable compatibility of medicine, assistant and guide, and suitable primary and secondary. The preparation method causes that the navel paste is refined in a larger level; that is to say the volume of the navel paste is reduced and the content of active ingredient in unit volume is increased, thus guaranteeing curative effect. By clinical observation, the navel paste has obvious curative effect in treating lax, enuresis, and sweating, thus proving the rationality of the prescriptions of the preparation and the preparation method. Meanwhile, the preparation is characterized by convenient use without any side effect and is especially suitable for the situation of difficult coordination on taking medicine and keeping taking medicine over a long time for infants.