Identification of modifiable intrinsic factors for occupational falls is required for initiating effective fall prevention strategies for older workers. This study aimed to identify modifiable intrinsic factors related to falls during occupational activities among older workers. This retrospective study involved 1164 older workers (aged ≥60 years, workdays ≥4/month) sampled from 18 public employment agencies for seniors in Saitama, Japan. Participants were assessed regarding the following 10 modifiable intrinsic factors: multimorbidity, polypharmacy, fall-risk-increasing medication use, self-rated vision and hearing, functional strength, bilateral stepping, standing balance, executive function and visuospatial ability. The number of falls during occupational activities in the past year was also recorded. In total, 111 falls occurred in 73 of the 1164 participants during occupational activities in the past year. A negative binomial regression model showed that use of fall-risk-increasing medications (incidence rate ratio [IRR]: 2.23, 95% confidence interval [CI]: 1.08, 4.60, P=0.031), reduced functional strength (IRR: 1.81, 95% CI: 1.02, 3.21, P=0.042), poor standing balance (IRR: 1.83, 95% CI: 1.09, 3.09, P=0.023) and poor visuospatial ability (IRR: 1.56, 95% CI: 1.03, 2.36, P=0.034) were independently associated with occupational falls. Our findings suggest that the assessment of medication use, functional strength, standing balance and visuospatial ability in regular health checks in the workplace may be useful for screening older workers at risk of occupational falls. Geriatr Gerontol Int 2022; 22: 338-343.