I need visa or not.and I also heard that we could get the transit visa too.

Hello,
I am from Nepal.And I have question about the transit visa.
on december I am going to my country(Nepal) its one way ticket.
I already have air tickets by china eastern airlines (MU).
And my flight schedules is like as below:

O5DECEMBER NARITA BEIJING 18:05 21:30 WEDNESDAY
06DECEMBER BEIJING KUNMING 06:40 10:00 THURSDAY
06DECEMBER KUNMING KATHMANDU 14:25 15:15 THURSDAY

could you help me with detail information.

Thanking you,
Bimala