Carcinogenic agents for nasal cavity and paranasal sinuses cancers (hereafter sinonasal cancers, SNC) with sufficient evidence in humans include nickel compounds and wood and leather dusts. Still limited evidence is available for carpentry and joinery, hexavalent chromium compounds, formaldehyde, and textile manufacturing. We studied occupational risk factors for SNC in a population-based case-control study nested in the SNC Registry of the Lombardy Region (10 million people), North-West Italy. SNC cases (or their next-of-kin) were interviewed using a standardised questionnaire. Controls (141 men, 64 women), taken form a recent population-based case-control study on mesothelioma, had been sampled among Lombardy residents (2014) and interviewed with the same questionnaire. We calculated odds ratios (OR) adjusted for the matching factors, smoking, and history of nasal polyps. We identified 386 SNC cases (2008–2014) with interview (256 men, 130 women). Among 105 adenocarcinoma cases we found ORs>30 for wood and leather dusts. Among 108 cases with mixed morphologies, we found elevated risks for wood (OR=2.2) and leather (OR=6.0) dusts. For both morphologies ORs for nickel, chromium, and formaldehyde were high but based on a few cases. Relative risks of adenocarcinoma and mixed morphologies were high in several sectors, including textile, construction, metal-mechanics, motor vehicle production, and agriculture and livestock. ORs for squamous cell carcinoma were elevated in agriculture and livestock only. In conclusion, we confirmed the strong associations between adenocarcinoma and wood and leather dusts, found elevated risk for mixed morphologies, and identified risk excesses in several sectors.