Abstract: Amaranth is a usual potherb nowadays. A lot of research work has been conducted on it, which covers macro and micro field, including the genetic resource, seed characteristics, physiologic characteristics, photosynthetic characteristics, medical value and pharmacological features. However, the knowledge on the original plants of the name of‘amaranth’is still lacking from the perspective of plant taxonomy. Data on ‘amaranth’were collected from history books and analyzed, the method of comparative morphology was adopted, and the scientific names were given based on the study. The research showed that there were 17 names associated with ‘amaranth’. Comparative study classified the names into three families: Amaranthaceae, Portulacaceae, and Euphorbiaceae. Plants in the Amaranthaceae included the Amaranthus albus L. and Amaranthus tricolor L., Achyranthes L. and Celosia cristata L.. The plant in the Portulacaceae was Portulaca oleracea L., and the plant in the Euphorbiaceae was Acalypha L. The research showed that it was in the Han Dynasty that the edible function of‘amaranth’plant had been discovered, and the time when Portulaca oleracea L. was put as an individual group clearly by Chinese was 800 years earlier than that by the European.