Assalaamu 'alaikum wa ra'hmatullaahi wa barakaatuhu, I know of a sahih hadith which states that if any male smells perfume of a woman in public places, he has to do fard ghusl, what is the ruling of it?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His Slave and Messenger.

A man is not obliged to perform Ghusl just for smelling perfume from a non-Mahram woman. There is no Hadeeth which makes this as an obligation. As far as we know, none of the jurists has ever said this. There is, however, a Hadeeth that forbids a woman from going out while wearing perfume. If a woman goes out wearing perfume, she has to wash her body so that the smell of her perfume fades away.

It was reported that a woman passed by Abu Hurayrah while she was wearing perfume (he could smell it from her), so he said to her, “O slave of Al-Jabbaar (The Formidable; one of the beautiful Names of Allaah)! Where are you going?" She replied, “To the Masjid.” He said, “And you perfumed yourself for it?” She replied, “Yes.” So, he said, “The Prophet said: “Any woman who goes out of her home wearing perfume and is heading to the Masjid, Allaah will not accept a prayer from her until she returns to her home and performs Ghusl from the smell of perfume in the same manner she performs Ghusl from Janaabah (ritual defilement).” [Abu Daawood and Ahmad]

The order for her to perform Ghusl is not because she is in ritual defilement but for the smell of the perfume to disappear. Al-Mubaarakfoori said in Sharh Al-Mishkaah: “Al-Qaari said that she should pour water over her entire body if she had perfumed her entire body in order that the smell of perfume disappears from her; but if she had applied perfume to a part of her body only, then she should wash that part only. I say, the Hadeeth is silent regarding this detail. Ibn Al-Malik said, 'This (ordering her to wash her entire body) is for emphasis on deterrence.'” [End of quote]

In addition, Abu Moosa Al-Ash’ari related that the Prophet said: "Any woman who applies perfume and passes by a group of people for them to smell the perfume is a fornicator.” [An-Nasaa'i and others] That is to say that she bears the same sin as that of a fornicator because the person who commits the cause that leads to  a sin is like the person who commits the sin. This is for emphasis on deterrence, as she incited the desire and lust of men by her perfume and led them to look at her, and whoever looks at her commits fornication of the eyes. So she is the cause of the fornication of the eye and is thus sinful.

For more benefit, please refer to Fatwa 93644.

Allaah Knows best.