The management of the two offices has been separate over the last ten years.
The director general of health and head of the ministry, Leausa Dr Take Naseri, said many difficulties had been noted in the running of the health service as a result.
His comments came after prime minister Tuila'epa Sa'ilele Malielegaoi met the two sides of the health service this week when he addressed several problems.
The minister of health is chairing an interim board of directors which includes the minister of finance, the attorney general and the minister of government enterprises to oversee the merger.
Leausa said combining the services would not affect jobs but could bring some health units under a single supervisory body.