The study was undertaken in Rewari and Sonepat district of Haryana to analyze factors influencing and various technological and socio-economic constraints to crop diversification. The study was based on both primary and secondary data. The primary data was collected from randomly selected 25 farmers each from randomly selected villages. The secondary source of data used pertains to the period 2006-07 to 2016-17. To determine the factors influencing crop diversification multiple linear regression model was used as its superiority over the other regression models and is easy to compute and interpret. Among the factors influencing crop diversification, age, education and size of land holding signicantly affected crop diversification in a positive manner while, income affected in a negative manner. To determine the technological and socio-economic constraints to crop diversification Garret’s ranking technique was used. Among the various technological and socio-economic constraints for crop diversification, lack of proper marketing facilities and lack of technical know-how were recorded to be the major constraints for crop diversification faced by farmers.