If a man puts his hand on your leg, it could mean several things depending on the context of your relationship and the situation. Here are a few possibilities:

Interest and Attraction: He may be expressing his romantic or sexual interest in you. This could be a way of establishing closeness or intimacy.

Comfort and Affection: If you have a close relationship, it might be a gesture of comfort or affection, indicating that he feels relaxed and connected with you.
Playfulness: Sometimes, touch can be playful. He might be trying to create a lighthearted atmosphere or engage in flirtation.

Assertiveness or Dominance: In certain contexts, touching could also be a way to assert control or dominance over the interaction.
Cultural Norms: Different cultures have varying interpretations of personal space and touch. For some, such a gesture may be normal and non-threatening.

Understanding his intentions can depend on your prior interactions and your comfort level with physical touch. Always trust your instincts and communicate your boundaries clearly if needed.