The Police Explosive Ordnance Disposal Team conducted Operation Render Safe on the un-exploded ordnance at Point Cruz.
A police statement said that this type of World War II shell is uncommon and has not been found before in Honiara's central business district.
The Solomon Star reported that the team isolated and secured the unexploded explosive shell on Tuesday after receiving a report from a construction group working there.
To remove it first requires it to be rendered safe by the properly trained unit.
Police said evacuating surrounding premises and implementing an exclusion zone, including road blocks, was necessary to keep the public safe.
The bomb was safely removed and police issued an all clear around 3:00pm local time.