Is it possible to hire taxi from kunming airport to dali old town?How much for this trip?

The distance is about 221 miles (350km). Instead of cab, you are suggested to charter a car for such a long distance. The fare may be around CNY 1,000.

Or, you can take shuttle bus line 5 to West Bus Station. Then, take a bus to Dali. The buses are available from 7:20 to 20:00, and the trip takes about 6 hours. The fare is CNY 110-137. ;)