The calculated distance (air line) between Phnom Penh and Kampong Cham is approximately 48 miles respectively 76 kilometers.
By car or train, the actual journey to Kampong Cham is certainly longer, as only the direct route (as the crow flies) between Phnom Penh and Kampong Cham has been calculated here.
Air line (approximately)
76 kilometers
41 nautical miles