<p>Hot cracking during laser welding of the aluminum alloy (AA) 6061-T6 adversely impacts the structural integrity and performance of welded joints. This study examined the effects of the beam inclination angle and welding speed on hot cracking during laser fillet welding of AA6061-T6 sheet lap joints. The welds were subjected to morphological and microstructural analyses, and their chemical compositions were determined. Good welds (without defects such as hot cracks and voids) were achieved using a beam inclination angle of 15°, moderate to high welding speeds (20–40&#xa0;mm/s), and a constant laser power of 1500 W. Microstructural analysis revealed that fine grain structures and small grain misorientation angles were associated with fewer hot cracks. Additionally, hot cracks exhibited a considerably higher silicon concentration (3.92%) than other regions. Microcracks and voids were subjected to microcomputed tomographic analysis. The small beam inclination angle (15°) reduced the amount of microvoids. These results demonstrate how hot cracking of AA6061-T6 fillet lap joints can be avoided.</p> Graphical Abstract <p></p>