In general, Cambodia is very safe for travelers. Violent attacks are rare, although theft is a problem. When possible, secure your valuables in the hotel safe. Remember to record your traveler’s check numbers and credit card info—just in case.
Do not leave your wallet or mobile phone in the back pocket of your pants or anywhere else that’s easily reached (like an outer zip-up compartment on a backpack). Be especially vigilant in markets and other crowded places like ports and train stations. Pick-pocketing and purse-snatching are more of a problem in Phnom Penh. Some thieves approach on motorcycles, grab your belongings and race off before you’ve realized what’s happened. If you ride in a cyclo (Pedi cab) do not hold your bag in your lap. Sit on it! Wearing valuable jewelry (especially necklaces that can be easily grabbed) is not advisable.
Use common sense and don’t walk alone after dark. There have been many reports of muggings in Phnom Penh late at night. If confronted by a mugger, do not resist. Siem Reap is much safer. You’re always better off skipping cyclos or motorbike taxis at night; ask your hotel or restaurant to call a reputable taxi firm or Tuk Tuk
Traffic is chaotic. If you choose to ride a motorcycle or bike, wear a helmet. When crossing the street on foot, move at a slow and steady pace. Fight the urge to weave and run! Walk slowly and traffic will flow around you.