Postal Service Employees' Political Activities Act of 1987

Postal Service Employees' Political Activities Act of 1987 - Declares it to be the policy of the Congress to encourage employees of the United States Postal Service to exercise their rights to participate or refrain from participating in political processes.

Prohibits such employees from: (1) using their official authority to influence the result of any election or the political action of any person; (2) using any information obtained through employment and not publicly available for any political purposes; (3) giving or offering to give a political contribution to any individual either to vote or refrain from voting; (4) soliciting or receiving a political contribution to vote or refrain from voting; (5) knowingly giving a political contribution to a superior; (6) knowingly soliciting or receiving a political contribution from another subordinate employee; or (7) knowingly soliciting or receiving a political contribution in specified facilities or from any person who has or is seeking business relations with the employee's agency. Directs the Postal Service and the Postal Rate Commission to prescribe certain exemptions to such prohibitions.

Prohibits employees from engaging in political activities while on duty, while wearing a uniform or official insignia identifying their position, or in designated areas.

Requires a postal employee to notify his or her agency (U.S. Postal Service or the Postal Rate Commission, as applicable) upon becoming a candidate for elective office. Permits such employee to take annual leave or leave without pay to engage in activities related to his or her candidacy.

Imposes penalties against employees found by the Merit Systems Protection Board to have violated this Act.

Requires the Postal Service to study and report to the Congress on the effects of this Act on the political activities of employees, the merit system, and matters generally contributing to the improper use of official authorities or information by employees.