To condition a wellbore with a reamer on a wireline, a portion of a wellbore is formed from a surface of the earth toward a subsurface hydrocarbon reservoir using a wellbore drilling assembly. After forming the portion of the wellbore, the wellbore drilling assembly is removed from the portion of the wellbore. Using a wireline, a wellbore sampling tool and a reamer are lowered into the portion of the wellbore. While maintaining the wellbore sampling tool and the wireline in a non-rotational state, the portion of the wellbore is cleaned using the reamer.