Jerry Farrell, 29, of Marston Road, Stafford, who admitted cruelty to the animal at a hearing on 2 June, was also banned from keeping pets for four years. Sentence had been adjourned for psychiatric reports.
Mid-Staffordshire magistrates were told Farrell had lowered the animal by its tail into the boiling oil as a friend watched.
The gerbil was heard splashing around in the fat and making 'squeaky noises', Christopher Lee, for the prosecution, said.
After frying it for several minutes Farrell put it on a saucer and took it to a neighbour's house.
Mr Lee said it had been a deliberate act which was towards the top end of the spectrum of cruelty cases.
When Farrell was seen by officers from the RSPCA he explained he had been feeling depressed and had been sniffing lighter fuel. He said he felt disgusted with himself and had never ill-treated his other pets.
A post-mortem examination revealed the gerbil's flesh was completely cooked. It had either scalded to death or drowned.
Robert Chadwick, for Farrell, said his client accepted his actions on 16 February this year were 'totally disgusting' and he was 'extremely remorseful'. But, Mr Chadwick said: 'He needs help, not punishment. He is a loner who has a considerable history of psychiatric illness.'
Mr Chadwick said because of publicity surrounding the case Farrell had received several threatening letters and he was afraid to go out on his own.
Farrell was also ordered to pay costs of pounds 250.