Also arrested during the raid were four residents who provided them with a hide out.
The Ethiopians, who do not speak English, were ordered to remain in custody when they appeared before a local court because there is no interpreter versed with their native language.
The Ethiopians, all aged between 20 and 30, entered the country without any form of identification and were being sheltered by locals, some of them cross-border transporters known locally as omalayitsha.
On Thursday, the all-men group were charged for entering the country illegally before Bulawayo magistrate Gladmore Mushove.
Prosecutors say all 12 come from Softah Village, Gesade Town, in Ethiopia.
They were transported, fed and housed by Gabriel Murindagomo, Nkosilathi Dube, Bhekani Dliwayo and Nqobile Ndebele who are now facing charges of assisting people to enter or remain in Zimbabwe illegally.
The magistrate postponed the case to December 10, telling the twelve: “I need to make consultations before I deliberate on this case.
“There’s a need to consider getting an interpreter since the 12 accused men do not understand English. They will remain in custody.”
The magistrate also ordered the four accused of transporting and sheltering them to return to court on Monday morning.
Prosecutors say the 12 illegals were dropped at Number 5847 Emganwini on Tuesday afternoon by a South Africa-registered Toyota Quantum.
Police from Nkulumane Police Station then received a tip-off and proceeded to the house where they rounded up all 12 with little resistance.
The police asked the men to identify themselves and they said they had no identity cards and that they were from Ethiopia.
Indications are that the 12 came to Bulawayo from Harare and were supposed to be ferried to South Africa via illegal crossing points.