Joedyn Luben, 32, had £77,000 in a safe at his home in Penlan, Swansea, he told Cardiff Crown Court.
He claims officers from South Wales Police stole £30,000 of this during the raid in April 2011.
Det Sgt Stephen Phillips, 47, of Swansea, Det Cons Christopher Evans, 38, of Llangennech, and Michael Stokes, 35, from Glynneath, deny theft.
Mr Luben told the court on Tuesday he gave the code to the safe to Det Con Stokes when asked by the officers.
He said he had been saving the money since he was 16 and last used the safe the night before the raid, when he deposited £12,000 following the sale of a car.
No action was taken against Mr Luben so a cheque was written for him to return his money.
However, he said this was £30,000 short of what was seized.
The case continues.
Three detectives stole a man's life savings in a raid on his home, a court has heard.