The incident took place between 3.20-5pm at a home in Tanglewood.
After entering through the window, they stole £250 and jewellery, including a Gucci watch and a Baume & Mercier watch.
Two white men wearing reflective jackets and a small white van were seen in the area at the time of the incident.
Police are appealing for witnesses to the incident.
Detective Sergeant Christina Berenger, from Local CID at Loddon Valley police station, said: “I would like to speak to anyone who may have any information about the above incidents.
“If any of the stolen property has been offered to you or you saw anyone acting suspiciously around the time of the incidents, then contact Thames Valley Police on 101.
“We are keen to trace a white van that is shaped similar to a small boxed shape van, whose occupants were seen acting suspiciously in Garston Grove, Finchampstead, on Monday, July 28. If you have seen this van around the area, contact us.
"It is very important that residents also check their home security and make any necessary changes to make their homes more secure. To do this I would request you to follow the crime prevention advice below.” Anyone with information should contact police on 101 or call Crimestoppers anonymously on 0800 555111.
Police have also issued advice guidelines to residents to ensure their home is safe and secure: - Ensure that windows and doors are closed and locked when you are out. Don’t leave small windows open believing them to be safe.
- If you want to leave windows open while you sleep, fit window restrictors so they cannot be fully opened, or make sure they are not large enough to allow access to a burglar.
- When out in your garden ensure that windows and doors to the front of the house are secure. It only takes a second for someone to get into your home and take things without you noticing.
- Do not leave valuables on display in front of windows or in reach of open windows or doors.
- Ensure that all barbecue and garden equipment and tools are securely locked up in a shed and out of sight. Tools can be used by the potential offender to break in to your home.
- Consider fitting outside security lighting or a visible alarm to help deter burglars. Even using pea shingle or gravel on a driveway and spiky plants in garden beds can help.
- Don’t leave any keys near entry points where they can be ‘fished’ or ‘hooked’ out through the window, letter box or cat flap.
- Ensure any internal handle operated locks on UPVC doors are fully secured with a key.