Federal Employees Paid Parental Leave Act of 2008

Federal Employees Paid Parental Leave Act of 2008 - Allows federal employees to substitute any available paid leave for any leave without pay available for either the: (1) birth of a child; or (2) placement of a child with the employee for either adoption or foster care. Makes available for any of the 12 weeks of leave an employee is entitled to for such purposes: (1) four administrative weeks of paid parental leave in connection with the birth or placement involved; and (2) any accumulated annual or sick leave.

Authorizes the Director of the Office of Personnel Management (OPM) to increase the amount of paid parental leave available to up to eight administrative workweeks, based on the consideration of: (1) the benefits provided to the federal government of offering increased paid parental leave, including enhanced recruitment and retention of employees; (2) the cost to the federal government of increasing the amount of paid parental leave that is available to employees; (3) trends in the private sector and in state and local governments with respect to offering paid parental leave; and (4) the federal government's role as a model employer.

Amends the Congressional Accountability Act of 1995 to allow the same substitution for covered congressional employees.

Amends the Family and Medical Leave Act of 1993 to allow the same substitution for Government Accountability Office (GAO) and Library of Congress employees.