Objectives <p>To identify the prevalence of workplace loneliness in Germany and to examine the factors associated with workplace loneliness.</p> Subject and methods <p>Cross-sectional data were used from a quota-based survey of the German adult population (representative in terms of gender, age, and federal state). We restricted our sample to individuals currently employed (<i>n</i> = 1975 individuals). Having feelings of loneliness at work “often” or “almost always” (on a 4-point scale) were defined as workplace loneliness. Multiple logistic regressions were conducted to clarify the factors associated with workplace loneliness.</p> Results <p>While 56.7% of respondents almost never felt lonely at work, 31.5% felt lonely occasionally, 8.1% felt lonely often, and 3.7% felt lonely almost always (corresponding to a prevalence of 11.8%). A high prevalence of workplace loneliness was particularly observed among individuals aged 30 to 39 years, individuals not living with their spouse/partner, individuals belonging to sexual minorities, and individuals with a migration background. Regressions showed that higher odds of workplace loneliness were consistently associated with poor health (in terms of unfavorable self-rated health and more chronic conditions) among the total sample and both women and men. Furthermore, it was associated with younger age group, having a migration background, and never drinking among the total sample and men.</p> Conclusion <p>Slightly less than half of the respondents feel lonely at work at least occasionally—more than one in ten report workplace loneliness often. Understanding the factors associated with workplace loneliness might assist in addressing those at risk.</p>