Ultrasonic instruments have an important role in the prediction of back fat depth of live pigs, mainly for the purpose of selecting animals for leaner pork production. Backfat in pigs consists of water, collagen, and lipid. Backfat thickness is one of the significant parameters to consider when selecting female pigs into breeding herds since it dominates a number of reproductive performances. The present study on measurement of back fat thickness (BFT) in thirty-six Landrace crossbred (62.5% Landrace and 37.5% Desi) live barrows and carcass was carried out at Swine production farm, Indian Veterinary Research Institute, Izatnagar, Utter Pradesh. The average BFT in live barrows was done by using back fat scanner one day before the schedule of slaughter and direct measurement of BFT in carcass were also observed after slaughter. In live barrows the BFT were measured at locations are midpoint of shoulder above elbow, middle of back where last rib joins the vertebrae and rump, straight above the stifle joint and average was calculated. The overall measurement of BFT of live barrows and carcass BFT (cm) were 1.81±0.44 and 2.12±0.08, respectively. The results showed that there was no significant difference of back fat thickness on live barrows and carcass were observed among the treatment groups. However, in dietary group had significantly highest back fat thickness measurement had been observed both live barrows and carcass. The BFT values were in values were in dietary group D3 (2.24±1.23), D2 (1.64±0.65) and in D1 (1.55±0.058) and in carcass D3 (2.59±0.12), D2 (1.92±0.10) and in D1 (1.85±0.058) respectively. However, values of BFT in lives barrows and carcass was almost similar. Based on this study it can be concluded that the Ultrasonic scanner is more reliable for prediction of BFT at growing stage of pigs and it can useful technique for selection of breeding stock for better genetic improvement and also for lean meat production.