To provide an agar weed extract whose characteristic smell is reduced and which can efficiently and homogeneously be mixed with a vegetable oil and the like, to provide a method for producing an agar weed extract, to provide a soap added with the agar weed extract, and to provide a method for producing a soap.

This agar weed extract is produced by filtering an agar weed-dissolved hot water, cooling the obtained liquid to solidify the liquid into the jelly-like product, subjecting the product to freezing, thawing and washing processes several times to deodorize and purify the product, heating the purified agar-agar fibers, cooling the heated fibers to solidify into a jelly-like product, and then crushing the product. The jelly-like agar weed extract is added to a sodium hydroxide aqueous solution and then mixed with an oil to produce the soap.