**Abstract**

Mutation is a sudden heritable change in the genetic material of living organism. Spontaneous mutation, the natural process that develops new allele copies of a gene was the only source of genetic diversity until the 20th century. Besides, mutations can also be induced artificially using physical or chemical mutagens. Chemical mutations received popularity due to its efficiency in creating gene mutations contrary to chromosomal changes. Mutation has played a vital role in the improvement of crop productivity and quality, resultantly > 3,000 varieties of 175 plant species have been developed either through direct or indirect induced mutation breeding approaches worldwide. The advances in plant breeding also achieved through molecular marker technology. The *in vitro* mutagenesis, heavy-ion beam, and space mutation breeding are being efficiently used to create genetic variability to improve various complicated traits in crop plants. In mutation breeding, TILLING (Targeting Induced Local Lesions in Genomes), a more advanced molecular technique is being used to identify specific sequential genomic changes in mutant plants. Therefore, the mutation breeding in combination with molecular techniques could be an efficient tool in plant breeding programs. This chapter will discuss and review the mutation breeding application for the improvement of crop productivity and environmental stresses.

**Keywords:** biotic and abiotic stresses, climatic changes, food security, ion beam, space mutagenesis, TILLING
