Thirteen far IR laser lines in CH
3OH, optically pumped by a CO
2laser, have been assigned to

- and

-type transitions in ν
5CO-stretch band. Identification procedures used were: a frequency match between the CO
2pump and CH
3OH absorption, frequency match of laser lines and CH
3OH ν
5transitions, polarization of far IR radiation, cascade and competition effects between far IR laser lines, and frequency consistencies. An improved set of molecular constants for ν
5transitions were also obtained.