The Putzmeister machine was stolen between 8pm on Friday 10 August 2012 and 8.30am on Monday 13 August 2012 at a building site on Sandbanks Road.
The machine is red and black in colour and is used to pump cement and self levelling floor screed.
The raiders forced the padlock on the main entrance gate before entering the building site in a getaway vehicle.
Debbie Oldfield, Crime Prevention Advisor, Bournemouth police, said: “This is a significant theft of a very expensive piece of building equipment that has obviously had a negative impact on the owners.
“We are keen to hear from anyone who may have seen anything suspicious in the area around the time of the incident.
“We would also like to hear from anyone who may have been offered a piece of equipment similar to this at an unusually low price or in strange circumstances.”