According to the Met police , the HP laptop was being used to show photographs of the boy during a service on November 2 at Pentecostal City Church, in Scrubs Lane, NW10.
After the funeral service, mourners left the church at around 1pm to go to Kensal Rise for the burial ceremony, but returned to discover the laptop was stolen.
Officers have now released CCTV footage of a man they wish to speak to in connection with the theft.
He is black, aged about 40, wearing a black hooded jacket, a white hooded top with writing on the front, blue jeans and walks with a distinctive limp.
Detective Constable Ben Kirkham from Hammersmith and Fulham CID said: "The church hall was left open after the congregation left for the burial. We have CCTV that shows a man walk into the building.
"After spending about 15 minutes inside he is then seen removing the laptop from the case and putting it into a carrier bag before leaving.
"The theft of this laptop with the father's precious photos of his son has obviously and understandably caused huge upset for the entire family who are already going through a very difficult time.
"If you recognise the man from the CCTV or have any information please contact police."
The laptop has a serial number of 8CG42003G6.
Anyone with information can contact 020 8246 2505.