The genetic relation of Quechua and Aymara has been maintained by some linguists and denied by others. Longacre and Orr have recently reconstructed the phonology. In this paper, further evidence is given using the method of positional reconstruction of categories, Aymara morphology is sketched and a comparison of the pertinent morphemes and positions of Aymara and Quechuapresented.Estudio comparado  de las lenguas quechua y aymara para demostrar que hay evidencia morfológica, fonológica y léxica de que estas dos lenguas están genéticamente relacionadas. Se utiliza un método propuesto por Hymes.