Background. We used the 2001 California Health Interview Survey (CHIS) to examine differences in cancer care access and utilization by subgroups of American Indian and Alaskan Natives (AIAN). Methods. The CHIS 2001 includes over 55,000 Californian households, with an oversampling of California American Indian, non-California AIAN, and unknown AIAN tribal groups. Results. We found significant differences among the 3 tribal subgroups for various measures of health care coverage and utilization. Conclusions. AIAN must be disaggregated to provide appropriate data for public health and policy making.