Yes they do have this service,
There are two categories of baggage storage at BIA.
- Bond Baggage Service - Valuable items and any other item which you need not take into the country could be stored subject to customs clearance at Bond Baggage counter located in the customs area in front of baggage belt No. 04. Bond Baggage fee is Rs 1000/- per baggage per day. On your departure, baggage could be collected at the Departure Lobby Information Counter.
- Left Luggage Service - Except perishable items, food items etc. could be stored at the left luggage counter located in the departure outer porch. Left Luggage fee is Rs. 100/- per baggage per day. Both counters are opened round the clock.