Central Contractor Registry Act of 2005 - Directs the Secretary of Defense to maintain a centralized, electronic database, to be known as the Central Contractor Registry, for the registration of sources of property and services (contractors) who seek to participate in contracts and other procurements entered into by various Federal procurement officials.
Requires the Registry to include certain tax-related information for each contractor, including their taxpayer identification numbers and authorization for the Secretary of Defense to obtain verification of such numbers from the Commissioner of Internal Revenue. Makes contractors who do not register such information, or who register invalid information, ineligible for contracts entered into under the Federal Property and Administrative Services Act of 1949.