Few analytical epidemiological studies have investigated family history (FH) of urinary tract cancers as a potential risk factor for renal cell carcinoma (RCC). A population-based case-control study involving 550 non-Asian RCC patients 25 to 74 years of age and an equal number of sex-, age-, and race-matched neighborhood controls was conducted in Los Angeles, California. Detailed information on FH of cancer, medical and medication histories, and other life-style factors was obtained through in-person interviews. Having a first-degree relative with kidney cancer was associated with a significantly increased risk of RCC [odds ratio (OR), 2.5; 95% confidence interval (CI), 1.04-5.9] after adjustment for potential confounding factors. Having a first and/or second-degree relative with kidney cancer was similarly associated with an increased risk of RCC (OR, 2.9; 95% CI, 1.4-6.3). Risk factors for RCC identified in the Los Angeles study include cigarette smoking, chronic obesity, history of hypertension, regular use of analgesics and amphetamines, intake of cruciferous vegetables (protective), and history of hysterectomy. None of the above risk factor-RCC associations differed significantly between RCC cases with and without a FH of kidney cancer. A FH of urinary tract cancers other than kidney cancer was not associated with RCC risk (OR, 0.7; 95% CI, 0.3-1.7). A FH of nonurinary tract cancers also was unrelated to RCC risk (OR, 1.1; 95% CI, 0.9-1.5).