The aircraft, owned by Pokhara Ultralight Company, had taken off at 10:35 am for the purpose of sight seeing and was out of contact after about an hour while flying near the Machhapuchhre Mountain, the police officer said.
The pilot was identified as 50-year-old Russian national Valerie Putin while the passenger is Elizabeth Well, 40, from South Africa, said Pokhara airport chief Dipak Baral.
The craft is missing since 11:30 am, according to a police officer.
Pokhara, a famous tourist hub of western Nepal, about 150 kilometres west of Kathmandu and flanked by the majestic Annapurna range, attracts thousands of visitors annually.