The company had sold 34,461 units during the same month last year, Tata Motors said in a statement.
Domestic sales of commercial vehicles in the month under review grew by 56 per cent to 36,806 units compared with 23,606 units in the year-ago period.
"Various macro-economic factors like improved industrial activities, infrastructure development and robust demand in private consumption-led sectors contributed to the growing volumes," Tata Motors Commercial Vehicles Business Unit President Girish Wagh said.
Passenger vehicle (PV) sales stood at 17,489 units last month as compared with 10,855 units in May 2017, up 61 per cent.
"Despite a challenging month, we have recorded a strong performance with a growth of 61 per cent. Thanks to the continued strong demand for Tiago and Tigor, our car sales recorded a growth of 18 per cent, while the UVs continued to record an exceptional performance of 463 per cent growth, due to the strong demand for the Nexon and Hexa," Tata Motors Passenger Vehicles Business Unit President Mayank Pareek said.
The company's exports last month stood at 3,699 units, down 5.15 per cent over 3,900 units last year.