A huge majority of prison warders and workers have signed a petition calling for Colonel Alex Dalli to return to his post as prisons director, according to the General Workers' Union.
In a post on Facebook on Wednesday afternoon, the union said 94% of all prison workers - 390 - had signed it.
"The workers of the Corrective Services Agency appreciate and thank Alex Dalli for his service," the union said.
"The agency workers are publicly acknowledging the great progress achieved under Dalli's leadership. The agency today has clear structures, order and sufficient resources to carry out its duties effectively."
Alex Dalli suspended himself on November 10, after a prisoner died by suicide in the latest of a series of such cases.
It was the 14th prison death in three years.
The inmate was Arun Jose, an Indian national working in Malta. He was found dead in his cell and prison authorities said they found a suicide note by his body.
Later that same day, two warders were charged with the involuntary homicide of another inmate, Kim Borg Nicolas Virtu, who also died by suicide in June.
In recent months, concerns have been raised about Dalli's leadership, with prisoners speaking out about inhumane and degrading treatment.
In its statement on Wednesday, the GWU said that for many years, the workers at the correctional facility and their families silently suffered from intimidation and a lack of resources but Dalli's prison leadership was instrumental in turning over a new page.
"In three-and-a-half years, the workers and Colonel Dalli managed to transform the facility from a place where drugs were the order of the day, to a place devoid of drugs and violence, thus facilitating inmate rehabilitation," it said.
The union listed infrastructural works and upgrades in prison under Dalli's stewardship, including a medical centre and the employment of 25 new professionals.
Earlier this week the Home Affairs Ministry confirmed that 10 inmates at the Corradino Correctional Facility had gone on hunger strike in support of Dalli.
It was reported that a number of inmates were circulating their own petition calling for Dalli's reinstatement.
However, on Tuesday the Nationalist Party claimed warders and inmates were facing attempts at intimidation for refusing to sign the petitions.