Among the most lucrative and quickly growing economic areas in the world- tourism, presents new opportunities for both developed and developing nations, towns, and territories. But it has also brought environmental consequences in its wake. The socioeconomic balance of the host nations as well as the long-term preservation of the environment depend heavily on sustainable tourism practices and ethical hotel management. Sustainable tourism and tourist behaviour are important for a city like Mussoorie which has seen a huge influx of tourists in recent years resulting in environment degradation and deterioration of the natural and aesthetic beauty of the place. This study in an attempt to examine the tourist sustainable behaviour and factors affecting visitors' willingness to pay more to stay in environmentally friendly hotels in the small city of Mussoorie which has shown problem tourist influx especially in peak seasons. It focuses on measurement of tourist behaviour while they are visiting the destination along with tourist’s perception about sustainability and sustainable tourism in general. The data was collected through primary survey with the help of questionnaire. It consisted of different sections including section for socio-demographic characteristic, preferences and attitudes of tourist and sustainable behaviour. The participants were selected from specific regions which have high tourist traffic and are popular for tourist visits. Individual tourists were approached to fill the questionnaire. Sustainable behaviour with regard to the regional economy, community and beliefs, and environment was measured using a after-visit indices based on 7 items concerning self-reported practices. Association between willingness to pay premium for green hotels, scores on the behavioural index with various other descriptors of tourists were examined using binary logistic regression models. Empirical results suggest that tourists who are older than 66 years of age tends to have low willingness to pay for green hotels and middle aged tourist showcases high sustainable behaviour scores. Travelling in large group sizes (more than 12 members) have a negative impact on tourist’s willingness to pay for green hotels and sustainable behaviour. However, the results suggest that years of education, gender and income has no effect on willingness to pay more. Subjective norm, perceived behavioural control, environment consciousness and awareness about environment problems positively influence tourist’s willingness to pay.