Two headed goals either side of the interval by Prince Dube and an 84th minute piledriver from substitute Wellington Taderera earned the Warriors a first leg victory in the third round African Nations Championship (CHAN) qualifier played at the National Sports Stadium on 22 September.
Lesotho scored a consolation away goal deep in added time when Mhlopo Kalake beat Simbarashe Chinani from the spot after the latter had been upended by Partson Jaure.
It could have been more goals for Zimbabwe had Dube managed to keep two of his lobbed shots down.
The win put Zimbabwe in a commanding position to secure a place at the CHAN finals in Cameroon.
The second leg will be played in Lesotho on 20 October 2019.