Alstroemeria L., one of the most diverse genera of the Chilean flora and of high floricultural value, is represented by 35 species, most of them distributed between 28-38 degrees S in the Mediterranean zone of Central Chile. There are 24 complex-forming taxa, of which 18 have conservation problems. One of these complexes is Alstroemeria diluta E. Bayer. with two subspecies: subsp. diluta and subsp. chrysantha Bayer. Alstroemeria diluta grows only in Chile; subsp. diluta is distributed from 34 degrees 15'S, Region of O'Higgins, to Cauquenes (36 degrees 00'S), Region of Maule, and subsp. chrysantha from 28 degrees 08'S, Region of Atacama, to Punta Curaumilla (33 degrees 05'S), Region of Valparaiso. A comparative karyotype study was carried out among four populations of A. diluta subsp. diluta and three populations of A. diluta subsp. chrysantha. The seven populations presented an asymmetric karyotype, with 2n = 2x = 16 chromosomes, and with same karyotype formulae: 3m + 1sm + 1st + 3 t. The architecture of the karyotype between the subspecies is the same. The scatter plot among MCA vs. CVCL shows different groupings between populations of the two subspecies, and the total chromosomes length (LTC) is highest in the populations of subsp. chrysantha. According to the results obtained, the populations growing in Valparaiso Region should be considered belong to subsp. diluta.