The present study has investigated the relationship between learning English vocabulary via mobile phone and the learners’ social anxiety and loneliness. The participants of the study were thirty-two intermediate English as foreign language (EFL) learners studying English at the University of Zanjan, Zanjan, Iran. Sixty American English idioms were chosen and became available in a Telegram channel, during a six-week period of treatment to provide the participants with Mobile-Assisted Language Learning (MALL). A researcher-designed achievement test was administered to assess the learners’ vocabulary learning via mobile phone. Interaction Anxiousness Scale (IAS) (Leary 1983) and UCLA Loneliness Scale version 3 (ULS) (Russell 1996) were used to estimate the learners’ social anxiety and loneliness, respectively. The results showed no significant correlation between the variables; thus, it can be concluded that MALL not only frees the learners from the restrictions of time and place, but also minimizes the possible intervention of some socially and emotionally affective variables, such as social anxiety and loneliness in the process of language learning. Keywords: Learning Vocabulary, Mobile-assisted Language Learning, Social Anxiety, Loneliness