Agriculture is the prime profession that helps in the overall development of the state economy.  Agriculture continues to be the important sector in the state economy as more than 56% of the people depend on Agriculture and allied sectors for their livelihood. Various steps taken by this Government to increase the investment in agriculture, Agri based technologies, marketing development, planning approach etc., has brought about substantial improvement in production inspite of seasonal vagaries like flood and drought. 

       Tamil Nadu occupies 7% of the nation's population, 4% of the land area and 3% of the water resources at all India level. The annual average rain fall at all India level is 1200 mm whereas the rainfall in Tamil Nadu is 930 mm. In this situation, the land and other natural resources are fully utilized in this State. The average land holding was 1.25 hectares during 1976-77 and it is 0.83 hectares as per 2005-06 census which is lower than the all India average of 1.33Ha. Thus, 91% farmers in Tamil Nadu are small and marginal farmers.   Of the total geographical area of 130 lakh hectares, around 51 lakh hectares are the net cultivated area. About 28.63 lakh hectares constituted the net irrigated area and the balance area of 22.37 lakh hectares is rainfed. In the area irrigated 26% area (7.53 lakh hectares) is under canal irrigation, 18% area (5.06 lakh hectares) under tank irrigation and 56% is (16.04 lakh hectares) under well irrigation. Totally there are 2,239 canals, 41,260 tanks, 18,32,154 wells and 78 dams in Tamil Nadu. 40% of the ground water potential and 3% of the surface water potential is utilized for cultivation. Only 97 blocks out of 385 blocks have full ground water potential.

Tamil Nadu has 7 agro climatic regions

Sl.No	Agroclimatic Zone	Districts
1	North Eastern Zone	Kancheepuram, Tiruvallur, Cuddalore, Vellore and Tiruvannamalai
2	Northern Western Zone	Dharmapuri, Salem and Namakkal
3	Western Zone	Erode, Coimbatore, Tiruppur, Karur, Namakkal, Dindigul and Theni
4	Cauvery Delta Zone	Trichy, Perambalur, Pudukkottai, Thanjavur, Nagapattinam, Tiruvarur and Part of Cuddalore
5	South Zone	Madurai, Sivaganga, Ramanathapuram, Virudhunagar, Tirunelveli and Thoothukudi
6	Hugh Rainfall Zone	Kanyakumari
7	Hill Zone	The Nilgiris and Kodaikanal (Dindigul)