The article continues the research connected with analysis of phonetic phenomena in modern Russian dialects of north-eastern part of the Republic of Mari El. This research is also connected with exploring of main tendencies which take place in the system of these dialects. The purpose of the research is to monitor modifications of affricates. The research done about half of a century ago by M. F. Moiseenko and some dialect materials collected by the author of the article for the last 10–15 years were the sources of this research. Analyzed dialect facts let us claim that Russian dialects of the Republic of Mari El belong nowadays to the group of dialects in which both affricates are distinguished. Affricates and are pronounced in standard way. However, there is the process of deaffricatization of and in some dialects of the North-East. For example, point affricate is replaced by voiceless fricative mild consonant . Our analysis proves that in modern dialects the loss of occlusive element by phoneme is an active process typival for speech of people of elder generation. Another dialect feature connected with the phoneme is depalatalization that is connected with the loss of occlusive element in and . Deaffricatization is observed in the phoneme : in this case the loss of occlusive element is happen. To sum up, the analysis of local phonetic material proves that some dialect phenomena remain in some dialects in spite of group of modifications. Also many dialect features are lost under the influence of the standard form of a language.