Vietnam topped the chart in 2013 with over 850,000 arrivals.
As many as 133,500 Cambodians were welcomed to Vietnam in January-March, up over 30 percent against the same period last year.
Tourism is one of the key economic sectors of Cambodia, enjoying an annual growth of 15-20 percent.
The country aims to serve around 4.7 million foreign tourists this year and 5 million in 2015, Thong Khon said.
It attracted 4.2 million overseas visitors last year, grossing 2.5 billion USD.
The country’s popular destinations are Angkor Wat Temple in Siem Reap, the Royal Palace in Phnom Penh and the ancient Preah Vihear Temple near the border with Thailand.
