whether govt. employee can avail LTA for his working spouse.

Husband is working in a government sector and wife is working in private company as contractual drawing 70,ooo/- p.m. Her company has certified that the company do not have the provision of LTA. Now is husband eligible to claim LTA for his wife from Govt. organisation in which he is working? Please comment.

Yes.
Govt servant can claim LTA for his wife, even if a private company for which she works gives LTA.
It is only when both are in govt service that such issues arise.

yes, when wife is in government service, LTA cannot be claimed. Unlike that she is in private company, LTA can be claimed.