The dead man, identified as 40-year-old Meet Singh Kapoor, was one of 35 people from Afghanistan, discovered at Tilbury Docks in Essex on August 16.
Police said a 47-year-old man from Dungannon in Northern Ireland has been arrested at Liverpool Ferry Port and will be transferred into the custody of Essex Police.
Two other men also charged in connection with the death remain in custody to appear at Basildon Crown Court in November.
The 34 survivors, including 10 men, nine women and 15 children with their ages ranging from one to 72, were found screaming and banging after arriving at Tilbury docks in Essex from Belgium.
The people who were rescued from the airtight container after an 18-hour ordeal are in care of the Home Office after being discharged from hospital and have sought asylum in the UK.
The survivors were hospitalised, many of whom suffered with severe dehydration and hypothermia.