NIRS provides rapid, simple, non-invasive and non-destructive phenotyping for rapid selection of traits for breeding. Standardization of spectra collection is important for replicability and hence comparability of different experiments. This SOP highlights the basics in NIRS as well as spectra collection in sweetpotato roots and potato tubers. The aim is to describe the method for spectra collection in different sample types for easy replication of the activities.