From a Jain point of view, marriage is a worldly matter, and there is no universal Jain rule that completely forbids a Jain girl from marrying a Hindu boy.

However, the important Jain consideration is this:

• Will the marriage support Jain values like ahimsa, satya, aparigraha, and restraint?
• Will the girl be able to continue Jain practices such as fasting, temple worship, pratikraman, and observing vows?
• Will there be respect for Jain faith, food rules, and religious observances?

So, it can be possible, but it should be done with clear mutual understanding and respect for Jain dharma.

In many Jain families and traditions, there is concern that interfaith marriage may weaken religious practice, so the family may not prefer it. Still, from the standpoint of Jain ethics, the main issue is not the label “Hindu” or “Jain,” but whether dharma and conduct are preserved.

If you want, I can also explain this from the Digambar and Shwetambar perspective.