BACKGROUND AND AIM. Testicular germ cell tumors (TGCT) are the most frequently diagnosed cancer in young men and their incidence rate has increased dramatically in recent decades. Occupational factors may play a role in testicular cancer etiology. This study aimed to further explore the association between occupation, industry, and the risk of TGCT in adulthood in France. METHODS. The TESTIS study included 454 histologically confirmed TGCT cases at ages 18-45 years. Controls (N=670) were frequency-matched to cases on 5-year age group and region. Occupational histories, with detailed description of each job, were ascertained through telephone interviews. Occupations were coded according to ISCO68, and industrial sectors according to NAF99. A manual backward stepwise selection procedure was performed to select the covariates to be included in our analyses. Odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for potential confounders, were estimated using conditional logistic regression. RESULTS. An increased risk of TGCT was observed for "machine fitters, machine assemblers" and "electrical fitters, electrical and electronic " workers (ISCO: 8-41; adjusted-OR = 2.46; 95% CI [1.08-5.62]/ISCO: 8-5; adjusted-OR = 1.80; 95% CI [1.11-2.91], respectively). Analyses by industry supported these findings. Moreover, an increased TGCT risk (adjusted-OR = 1.71; 95% CI [1.02-2.82]) and non-seminoma risk (adjusted-OR = 2.12; 95% CI [1.11-4.04]) was identified for "agricultural and animal husbandry workers” (ISCO: 6-2). CONCLUSIONS. Our results suggest that occupational exposures may be associated with an increased risk of TGCT in agricultural, machine, and electrical/electronic workers in this population. Our findings were consistent with previously published studies. Since these jobs may involve exposure to a variety of potential carcinogens/endocrine disruptors, such as pesticides and solvents, complementary studies with the application of job-exposure matrices will allow an in-depth evaluation of the role of the substances involved in the high-risk professions identified. KEYWORDS. Occupation, epidemiology, testicular cancer, agriculture