It is noted that one language may have an influence in learning the other language. This influence may be vividly seen in different aspects such as phonology, morphosyntax as well as lexis. This paper focuses on investigating how the Ethnic Community Languages, henceforth ECLs, can phonologically influence the learning process of Kiswahili language. Kinyakyusa was taken as a sample to represent other Ecls in Tanzania to see its phonological influence in Learning Kiswahili. The study employed word lists, in depth interview and observations as data collection techniques. The findings revealed that, phonologically, speech sounds that are similar in Kinyakyusa and Kiswahili as a second language such as /p/, /t/, /k/, /f/, /s/ were easily learned. Learners were faced with some difficulties in pronouncing some utterances that are not found in Kinyakyusa but exist in Kiswahili. For instance, voiced alveolar trill sound /r/ was pronounced as voiced alveolar lateral sound /l/, voiceless dental fricative sound /θ/ was pronounced as voiceless alveolar fricative sound /s/.