Medicare Mental Health Modernization Act of 2000 - Amends title XVIII (Medicare) of the Social Security Act (SSA) to: (1) repeal the current formula for calculating expenses for treatment of mental disorders; and thus (2) provide for Medicare beneficiary copayments for outpatient mental health services that are the same as beneficiary copayments for other Medicare part B (Supplementary Medical Insurance) services.

Amends Medicare part A (Hospital Insurance) to provide for coverage of intensive residential services.

Directs the Secretary of Health and Human Services to study and report to Congress on whether the criteria for Medicare coverage of any therapy service (including occupational and physical therapy) or any outpatient mental health care service unduly restricts the access to such a service of any Medicare beneficiary diagnosed with Alzheimer's disease or a related mental illness because the coverage criteria requires the beneficiary to display continuing clinical improvement to continue to receive the service.

Amends Medicare to: (1) cover mental health counselor services; and (2) exclude clinical social worker services from coverage under the Medicare skilled nursing facility prospective payment system.