A well-developed root system is essential for efficient nutrient and water uptake. Evaluating the variability for root traits and identifying the genomic regions can aid in the development of nutrient use/water use efficient cultivars with better yields. We phenotyped a set of homozygous BC2F12 backcross introgression lines (BILs) developed by crossing the durum wheat cultivar PDW274 (2n=4x=28; AABB) and diploid wild relative Aegilops speltoides (2n=2x=14; SS) for various root architecture traits during two consecutive years 2019-20 and 2020-21. The roots were sampled at the maximum tillering stage using a shovel and the sampled roots were washed and used for root scanning and image analysis using the WinRHIZO software. Data on various root architecture traits namely, total root length (TRL), root surface area (RSA), root projected area (RPA), root volume (RV), average root diameter (ARD), number of root tips (NRT), number of root forks (NRF) and number of root crossings (NRC) were extracted. Data on root dry weight (RDW), shoot dry weight (SDW) and grain yield (GY) were also recorded. Analysis of the two-year root phenotyping trials revealed considerable variability for all the recorded traits. The traits TRL, RSA, RPA, RV and RDW displayed a moderate positive correlation with grain yield. The BILs were genotyped using genotyping-by-sequencing to obtain 5,672 high-quality polymorphic SNPs. The BLUPs of the root phenotypic data were computed and used for the QTL mapping along with the genotypic (GBS) data in the QTL Ici mapping v4.2 software using the ‘CSL’ functionality. Twenty-one QTLs were detected for various root architecture traits on chromosomes 1A, 2A, 2B, 3B, 5A and 6B. The phenotypic variance explained (PVE) ranged from 5% to 18.2%. Pleiotropic QTLs were detected on chromosomes 1A, 2A and 2B indicating coordinated control of closely associated genes. Three stable QTLs QTrl.pau-As-2A, QNrt.pau-As-2B.2 and QRdw.pau-As-3B were detected consistently in both years. Scanning of the 1 Mb region flanking the mapped SNPs linked to the stable QTLs revealed multiple genes involved in root growth and development. These QTLs can be used in breeding programmes after the development and validation of suitable marker assays. The BILs can be used for further studies by subjecting the roots to drought, salinity or nutrient stresses to identify the genetic mechanisms controlling root plasticity under these stresses.