We revisit predictions about the relationship between gender diversity and firm productivity using data on 1,082 manufacturing firms from six Sub-Saharan African countries: Ghana, the Democratic Republic of Congo, Tanzania, Uganda, Zambia and Kenya. Recent evidence suggests that a gender-diverse workforce opens up a firm to a vast range of talent, knowledge and perspectives critical to enhancing innovation and problem solving, and thereby, increasing firm productivity. Given the importance of manufacturing for employment and structural transformation in Africa, we test the gender diversity–productivity proposition by exploring structural differences (heterogeneity) across manufacturing firms using the Industry without Smokestacks (IWOSS) classification. We find that while gender diversity promotes firm productivity at lower levels, this effect is displaced with further increases. Our results did not show that IWOSS firms do any better in promoting the diversity–productivity link. Implications of this finding and areas for future studies are also discussed.