चेन्नई हा दक्षिण भारतातील एक प्रमुख व्यापार-व्यापार आणि रहदारी केंद्र आहे. १९ व्या शतकाच्या शेवटी चेन्नईमध्ये औद्योगिक क्षेत्राची स्थापना झाली. आशियातील सर्वात मोठी रेल्वे कोच निर्मिती कारखाना, इंटिग्रल कोच बिल्डिंग फॅक्टरी, भारत सरकारने चेन्नईजवळील पेरंबूर येथे स्थापित केली आहे. इथल्या उद्योगांमध्ये सुती वस्त्र उद्योग, रसायन उद्योग, कागद व कागदावर बनविलेले उद्योग, मुद्रण उपकरणे व संबंधित उद्योग, चामड्याचे, डिझेल इंजिन, मोटार वाहन, सायकली, सिमेंट, साखर, मॅचमेकिंग, रेल्वे कॅनिंग उद्योग इ. प्रमुख आहेत. या व्यतिरिक्त, विविध प्रकारचे उद्योग व सरकार चालवणारे कारखाने चेन्नईमध्ये आहेत. त्यापैकी इंटिग्रल कोच फॅक्टरी, हिंदुस्तान टेलिप्रिन्टर, चेन्नई रिफायनरी आणि चेन्नई फर्टिलायझर इ. पेट्रो-केमिकल सामग्रीची निर्मिती मद्रास पेट्रोकेमिकल्समध्ये केली जाते.. . 

The city is base to around 30% of India's automobile industry and 35% of its auto components industry. A large number of automotive companies including Hyundai, Ford, BMW, Mitsubishi, Komatsu, The TVS Group (TVS), Ashok Leyland, Nissan-Renault, Daimler Trucks, TI Cycles of India, TAFE Tractors, Royal Enfield, Caterpillar Inc., Caparo, Madras Rubber Factory (MRF) and Apollo Tyres have or are in the process of setting up manufacturing plants in and around Chennai. The Heavy Vehicles Factory at Avadi produces military vehicles, including India's main battle tank: "Arjun MBT". The Integral Coach Factory manufactures railway coaches and other rolling stock for Indian Railways. This very industrial expanse has given the name to Chennai as being the "Detroit of Southern Asia". The Ambattur-Padi industrial zone houses many textile manufacturers, and an SEZ for apparel and footwear manufacture has been set up in the southern suburbs of the city. Chennai contributes more than 50% of India's leather exports.

Many software and software services companies have development centres in Chennai, which contributed 14% of India's total software exports of Rs.144,214 crores during 2006–07, making it the second-largest exporter of software in the country, behind बंगळुरू. Major software companies like TCS, Infosys, Wipro, Hewlett Packard, HCL, आय.बी.एम., Satyam, CTS, MphasiS, Polaris Software Lab, Capgemini and Accenture have their offices set up here, with some of them making Chennai their largest base. Prominent financial institutions, including the World Bank, Standard Chartered Bank and Citibank have back office operations in the city. Chennai is home to three large national level commercial banks and many state level co-operative banks, finance and insurance companies. Telecom giants Ericsson and Alcatel-Lucent, pharmaceuticals giant Pfizer and chemicals giant Dow Chemicals have research and development facilities in Chennai. TICEL bio-tech park and Golden Jubilee bio-tech park at Siruseri house biotechnology companies and laboratories. Chennai has a fully computerised stock exchange called the Madras Stock Exchange.

भूगोल
अर्थव्यवस्था
सेवा-सुविधा
इतिहास