N-Aryl-3,4-dihydroisoquinoline carbothioamide analogues 1-22 were synthesized by a simple one-step reaction protocol and subjected to in vitro urease inhibition studies for the first time. All compounds 1-22 were found active and showed significant to moderate urease inhibitory potential. Specifically, analogues 1, 2, 4, and 7 were identified to be more potent (IC50 = 11.2 ± 0.81-20.4 ± 0.22 μM) than the standard thiourea (IC50 = 21.7 ± 0.34 μM). The structure-activity relationship showed that compounds bearing electron-donating groups showed superior activity. Molecular docking study on the most active derivatives revealed a good protein-ligand interaction profile against the corresponding target with key interactions, including hydrogen bonding, hydrophobic, and π-anion interactions.