Ambarawa Hospital, Semarang Regency, was established in 1930, owned by the Catholic Foundation during the Dutch East Indies Government, then in 1945 some of the management was handed over to the Level II Regional Government and in 1956 the whole hospital was handed over to the Level II Regional Government of the Regency. Semarang.

According to the Decree of the Minister of Health of the Republic of Indonesia Number: 203/Men Kes/SK/II/1993, dated February 23, 1993 and the Decree of the Regent of the Head of the Level II Region of Semarang Regency No: 203/2017/1993 the Ambarawa Hospital was changed to a Type C Hospital.

The Organizational Structure and Work Procedure of the Ambarawa Hospital was first obtained in 1995, namely based on the Regional Regulation of the Second Level Regional Regency of Semarang Number 28 of 1995 concerning Guidelines for the Organizational Structure and Work Procedure of the Semarang Level II Regional General Hospital.

Based on the Decree of the Regent of the Head of the Second Level Region of Semarang Number 4 of 1999 and the Approval of the Minister of Home Affairs Number 445/303/PUOD, RSUD Ambarawa became a Regional Self-funded Hospital with a bed capacity of 140 TT.

Based on the Decree of the Regent of Semarang No. 4 of 2002 and the Decree of the Minister of Home Affairs No. 29 of 2002, RSUD Ambarawa became a Regional Self-funded Hospital with a bed capacity of 154 TT.

Based on the Decree of the Regent of Semarang No. 1 of 2004 the self-funding management of the Ambarawa Hospital was revoked, it was proposed to obtain a new Organizational Structure and Work Procedure.

Based on the Regional Regulation of Semarang Regency Number 20 of 2005 dated January 4, 2005 concerning the Organizational Structure and Work Procedure of the Ambarawa Hospital with the structure of the Head of the Ambarawa Regional Hospital Echelon IIb.

In 2008 RSUD Ambarawa underwent changes in the Organizational Structure and Work Procedures based on the Regional Regulation of Semarang Regency Number 19 of 2008 dated January 4, 2008 concerning the Organizational Structure and Work Procedure of the Ambarawa Hospital.

In 2011 RSUD Ambarawa underwent a change in the Organizational Structure and Work Procedure based on the Regional Regulation of Semarang Regency Number 3 of 2011 dated January 4, 2011 concerning the Organizational Structure and Work Procedure of the Ambarawa Hospital.

In 2011 RSUD Ambarawa became PPK-BLUD with full status based on the Decree of the Regent of Semarang Number 445/0529/2011 dated October 27, 2011 concerning the Determination of the Application of Financial Management Patterns for Regional Public Service Agencies (PPK-BLUD) with full status.

RSUD Ambarawa is owned by the Government of Semarang Regency which is located at Jalan Kartini No. 101 Ambarawa, Semarang Regency, with a land area of ​​12,000 m2. The arrangement of the existing buildings is still in the development stage to meet the demands for capacity and quality of service that is growing rapidly, both from an internal (health care provider) and external (visitor and patient) side of the hospital.

The Regional General Hospital (RSUD) Ambarawa from time to time in providing services to customers runs smoothly and gains the trust of various parties. This condition can not be separated from the consistency of RSUD Ambarawa towards hospital development efforts based on the vision of RSUD Ambarawa: "To become a quality, trusted, and proud hospital for the community".

RSUD Ambarawa obtained the achievement of passing the Accreditation of 16 Services on January 3, 2012 with Certificate Number: KARS – SERT/271/1/2012. 1st Place in the Image Competition for Excellent Service at Semarang Regency Level. On November 10, 2014, RSUD Ambarawa received ISO 9001:2008 accreditation for medical records, emergency department, outpatient services including perinatology and gynecology, laboratories, pharmacy, radiology, ICU, IBS, nutrition, and supporting processes.

In 2020 there was a change in the name of the Ambarawa Hospital to dr. Gunawan Mangunkusumo Hospital based on the Decree of the Regent of Semarang Number 180 / 0094 / 2020.