Relevant time series data/information on temperature, rainfall and relative humidity over considerable period of about 4 decades has been analysed using simple statistical tools such as periodic mean, mean deviation and t-test to ascertain the changing climate pattern in Ludhiana district of Punjab. During past 40 years, the region experienced significant increase in average minimum temperature for all months in kharif season in the range of 1.4-2.1°C. The average maximum temperature has increased only for the month of August (0.5°C), while it decreased for the months of June (1.4°) and September (0.6°C). In totality, rise in average monthly temperature during kharif season has enhanced the level of warming. The average rainfall of the region showed an increasing trend with significant results for September (46.7 mm) and October (15.2 mm). The average relative humidity during the study period has been consistently and significantly increased in the range of 1.5-10 per cent during all these months. Climate change has the ability to influence the crops productivity either positively or negatively. Most of the studies have utilised various simulation models to estimate the likely impact of climate change on paddy productivity, while very few studies have considered how rising temperature and erratic rainfall or as a whole changing climatic factors have actually affected crop productivity and production. Weekly correlation between each climatic factor and periods of the crop season were computed to develop the empirical relationship and to identify all potential weeks climate affecting paddy productivity. The study identified climatecomposite technological index model as a better fitted model to describe the impact of climate as well as technology on paddy productivity in Ludhiana district of Punjab. Increase in the maximum temperature has negative impact on paddy productivity, while increase in the minimum temperature, rainfall and relative humidity has positive impact though non-significant.