Two new species of the genera Uroleucon Mordvilko 1914 and Pleotrichophorus Börner 1930 are described from Kazakhstan. Uroleucon dzhungaricum sp. n. living on Senecio nemorensis L. (Asteraceae) in the Dzhungar Alatau is described. U. dzhungaricum sp. n. is close to U. minor (Börner 1940). Both these species differ from the close U. solidaginis (Fabricius 1794) species by a smaller ratio between processus terminalis and the third antennal segment (0.8-1.0 versus 1.0-1.5). The new species differs from U. minor (Born.) by the larger number of secondary rhinaria on the third antennal segment of apterous viviparous females (21-37 versus 15-21), fewer number of hairs on cauda (10-16 and 15-23), and another host plant. Pleotrichophorus ugamicus Kadyrbekov sp. n., living on Artemisia santolinifolia Turcz is described from Sairam-Ugam Natural Park (southern Kazakhstan). The new species is similar to P. glandulosus (Kaltenbach 1846) and P. achilleae Holman 1965. Pleotrichophorus ugamicus sp. n. differs from them by the ratio of processus terminalis to the base of the sixth antennal segment (4.1-5.0 versus 5.0-9.0 and 5.1-6.2), the ratio of the ultimate rostral segment to the second segment of hind tarsus (0.68-0.76 versus 0.80-0.97 and 0.80-0.90), and by another species of host plant. This species differs from P. glandulosus in the ratio of the length of dorsal hairs on tergites 1-5 to the basal diameter of the third antennal segment (1.0-1.2 and 1.4-1.7). In addition, the new species differs from P. achilleae by the ratio of the third antennal segment to the sixth segment (0.56-0.66 versus 0.70-0.87) and to processus terminalis (0.67-0.82 versus 1.39-1.80), as well as by the form of dorsal hairs. A key to identify Palearctic species of the genus Pleotrichophorus is presented.