Mycobacterium infection caused by Mycobacterium tuberculosis (MTB) and non-tuberculosis mycobacterium (NTM) presents a serious threat to global health, mainly due to a protracted treatment regimen involving a combination of drugs. Antibiotic resistance in mycobacterium is mainly due to a frequent gene mutation that encodes antibiotic resistance. There are also several additional unique features of drug resistance, such as chromosomal mutation, efflux pumps, bacterial heterogeneity, slow metabolism, biofilm formation, antibiotic degradation or modification, target modification, and host microenvironment. In this chapter, we discuss the traditional mechanisms of drug resistance in mycobacterium, newer understandings, and the shaping of unconventional approaches to target both the emergence and treatment of drug resistance in mycobacterium.