A new species of Etropus, E. ciadi, is described, and it is characterized by the following combination of characters: small size (maximum 92.7 mm SL); body depth generally more than 50% SL (47.1–60.6%, only 1.6% of 243 specimens less than 50%); head relatively small (22.1–26.6% SL); deciduous scales without small accessory scales on exposed surface; teeth feeble and mobile; 66–79 and 52–62 dorsal-and anal-fin rays, respectively; 36–43 lateral-line scales; pelvic-fin rays nearly always 6; gill rakers 2–7 5–10 on first arch; dark brown speckles on body and dorsal-and anal-fin rays. Of its eastern Pacific congeners, E. ciadi is most similar to E. crossotus. Etropus ciadi is endemic to the Gulf of California and lives on soft bottoms in shallow depths (8–40 m), from Rocas Consag, Baja California, (31°18.2′ N, 114°25.0′ W) to Bahía Altata, Sinaloa (ca. 24°36′ N, 107°55′ W).