Preventive Health Block Grant Act - Amends title III (General Powers and Duties of Public Health Service) of the Public Health Service Act to replace the current grant programs for health planning and public health services, preventive health services, paint poisoning, and venereal disease with a Preventive Health Block Grant program. Authorizes specified appropriations for fiscal years 1982-1985. Sets forth the allotment formula and application requirements.

Authorizes the use of funds for health promotion and disease prevention including technical assistance. Prohibits the use of funds for: (1) cash payments to health services recipients; (2) construction or land purchase; and (3) satisfying non-Federal funding requirements.

Authorizes any State to transfer up to ten percent of block grant funds for use under other Federal law providing for health or social services, or for meeting home energy and emergency assistance needs.

Requires States to: (1) report on intended expenditures; and (2) report and to prepare an audit at least every two years concerning activities under this Act.

Repeals various Federal laws authorizing categorical grants and other assistance in related areas.