Nueva Ecija is one of the top producers of agricultural products in the country. Its principal crops is mainly rice but corn and onion are also produced in quantity. The province is often referred to as the “Rice Granary of the Philippines.” Other major crops are onion, mango, calamansi (calamondin orange), banana, garlic, and vegetables. The town of Bongabon at the eastern part of the province at the foot of the Sierra Madre mountains and its neighbouring Laur and Rizal are the major producers of onion and garlic. Bongabon is called the "onion capital of the country".
Education is very well established as a major industry in the province. The leading educational institutions are the Central Luzon State University in Munoz and Nueva Ecija University of Science and Technology, Wesleyan University-Philippines, La Fortuna College and Araullio University in Cabanatuan. There are 18 tertiary level institutions in Cabanatuan City alone.
Health services is also a notable industry and a number of hospitals cater to patients from within Nueva Ecija and some coming from neighbouring provinces. There are also a number of schools of nursing and midwifery, mostly in Cabanatuan.
There are poultry farms in a number of towns, most notably, the Lorenzo poultry farms in San Isidro which is one of the largest in the country. Duck raising and egg production is also an important livelihood. Fishponds are unevenly distributed throughout the province but the largest concentrations are in San Antonio, Santa Rosa, and Cuyapo.
Fabrication of tricycle "sidecars" is widespread in the province, notably in Santa Rosa, where prices are as low as PhP 7,000 which is practically the cheapest in the country.
Several areas have mineral deposits. Copper and manganese have been found in General Tinio, Carranglan, and Pantabangan. The upper reaches of Carranglan and Palayan City are said to contain gold.
In June 2008, it has also received the title: "Milk Capital of the Philippines" due to the reason that Nueva Ecija gathers more milk from both cows and carabaos or water buffaloes than any other place in the Philippines. The Philippine Carabao Center is located in CLSU compound in Munoz City.