"He is not worth <gerund>" is a statement about return-on-investment. "He is not worth robbing" means that the effort and risk to break in and rob the guy is greater than the likely profit you'll make on the crime. "He is not worth helping" means that the time and effort you put into helping him will not be appreciated, so you might as well not bother. "He is not worth disturbing" would only make sense if you could similarly compare the investment needed to disturb someone, with the potential reward for doing so. I'm not sure I could do that, unless we're talking about sheer malicious fun of bugging a person. Anyway, to me, it doesn't make sense. I think what you're probably after is "He is going through an extremely difficult time, so please don't disturb him."

Sabina, your sentence is grammatically correct. but the second part "he is not worth disturbing" is slightly humorous.

The sentence is grammatically correct, but the second half has a poor connotation. Saying that something is "not worth it" has a negative meaning, especially when talking about a person. If he is "not worth" disturbing, the speaker implies that he is a worse talking partner than any other person. The result is that the statement might be viewed as mean or insensitive to the man. Try expressing the fact that he shouldn't be disturbed without bringing worth or value into the sentence: "He is going through an extremly difficult time. Please do not disturb him." "He is going through an extremly difficult time, so please do not bother him." "He is going through an extremly difficult time, so please leave him alone." We try to convey respect for the person being spoken about. That is, we don't want to seem as if we are insulting them, so we phrase the sentence to express that disturbing the man would be worse for the man instead of worse for the person trying to disturb him. This sounds less selfish to the listener.

The first part is ok, I just don't really understand what "he is not worth disturbing" means. Do you mean to say: "don't bother him"?