The New York-listed company, which has about 60 per cent of India's USD 5 billion truck and bus market, said net profit rose to 4.67 billion rupees (USD 116 million) in the fiscal first quarter to end-June from 3.82 billion a year ago.
The result beat a Reuters poll forecast for 3.57 billion rupees.
Tata Motors, also India's third-biggest car maker behind Maruti Udyog Ltd and South Korea's Hyundai Motor Co, has a joint venture with Italy's Fiat to make cars and engines in India and a separate venture for trucks.
It is scheduled to roll out a cheap small car in 2008 and has a pick-up truck joint venture with Thailand's Thonburi Assembly.
Shares in Tata Motors, valued at more than USD 7 billion, fell 8 per cent in the June quarter, trailing a 2.7 per cent fall for the sector index and a 12 per cent gain for the main index.