The calculated distance (air line) between Phnom Penh and Tbeng Meanchey is approximately 155 miles respectively 250 kilometers.
By car or train, the actual journey to Tbeng Meanchey is certainly longer, as only the direct route (as the crow flies) between Phnom Penh and Tbeng Meanchey has been calculated here.
Air line (approximately)
250 kilometers
135 nautical miles