Lung cancer rates in Israel are lower than in Western countries, not explainable by smoking habits. Because of the different relations of squamous cell carcinoma and adenocarcinoma to smoking it was of interest to study the histologic distribution in Israel. A total of 7,871 histologically confirmed lung cancer cases were studied in the period 1962-1982. Squamous cell carcinoma was the leading tumor type in Jewish men and adenocarcinoma in Jewish women. Rates of both adenocarcinoma and squamous cell carcinoma increased throughout the period in both Jewish men and women, but the increase in adenocarcinoma was more pronounced in the last study period than that in squamous cell carcinoma. In 1977-1982 the rate ratio of squamous cell carcinoma to adenocarcinoma among Jewish men was 1.7. In Arab men it was 2.9, and in Jewish women 0.57. The Kreyberg I/II ratio among Jewish men was about 2.7 with no clear trend throughout the study period, and among Arab men this gradually decreased from 8.1 to 3.5. Jewish women had a constant Kreyberg I/II ratio of about 1 through the whole study period, but the ratio in Arab women was significantly higher than 1, with a mean overall ratio of 3.2. Jews and Arabs in Israel are different from each other in their patterns of lung cancer histology and are different to some extent from other populations in the Western world.