The cost of a 1-acre mango farm in Chennai can vary depending on several factors such as location, soil quality, water availability, and the age and variety of mango trees planted.

In general, the cost of a 1-acre mango farm in Chennai can range from anywhere between several lakhs to a few crores of Indian Rupees. Additionally, ongoing expenses such as labor costs, fertilizers, and irrigation systems will also need to be factored in.