He was the sixth child of a Pangasinense father, Eusebio Velasquez, and a Caviteña mother, Andrea Santos.

In 1928, Velasquez – together with script writer Romualdo Ramos – created Kenkoy, a “Filipino comic star” character that first appeared in the Tagalog-language Liwayway magazine on 11 January 1929.

[1] In 1932, he also created the female equivalent of Kenkoy, Ponyang Halobaybay, a typical portrait of the Filipina woman in American-era Philippines.

[1] In 1947, Velasquez retired from Liwayway magazine to create the publishing firm Ace Publication, a mass producer of Philippine comic books.

[1] Velasquez was the mentor to other Filipino illustrators, namely Francisco Coching (who later became a National Artist for Visual Arts in 2014), Mars Ravelo, Jose Zabala-Santos, and J. M. Perez, among others.