The present article investigates the phonological processes in three Balochi Dialects of Iran (BDI), namely, Sarhaddi Mirjaveh Balochi (SMB), Sarawani Balochi (SB), and Lashari Balochi (LB). In addition, analyses of these phonological processes are given in the framework of optimality theory (OT). The data extracted from the linguistic corpus was collected through fieldwork in Sistan and Baluchestan province, Iran. The research findings show that phonological phenomena in BDI include both local and long-distance consonant metathesis, local assimilation such as voicing assimilation, nasal place assimilation and complete assimilation, voicing dissimilation, hiatus resolution by inserting /j/ or /ʔ/ between heterosyllabic vowel sequences, and final consonant (voiced stops and affricates) devoicing.