The investigations entitled “Spectrophotometric analysis of nectar sugar composition by different bee plant species” were carried out at G.B. Pant University of Agriculture and Technology, Pantnagar during the year 2020-21. Among the three species of mustard, highest total sugar content (0.384±0.018 mg/flower) was recorded at 24 hours of flower opening in B. rapa var. yellow sarson, while minimum total sugar content was recorded just after opening of flowers (0 hours). Mean sugar concentration per flower was highest (33.34 per cent) in B. rapa var. toria, whereas least (27.26 per cent) in B. juncea. The total energy present per flower per day was highest in B. rapa var. yellow sarson with 0.37; 6.43; 8.63 and 4.58 J/flower/day at 0; 24; 48 and 72 hours respectively, and least in B. rapa var. toria with 0.25; 4.84; 3.88 and 2.75 J/flower/day at 0; 24; 48 and 72 hours. Furthermore, highest mean nectar sugar composition of glucose (51.33±0.41) was recorded in B. rapa var. toria, fructose in B. rapa var. yellow sarson (44.27±0.35) and highest sucrose concentration was found in B. juncea (0.605±0.047). Among the other eight bee forage plant species, berseem flowers were found to be richest floral nectar resource with highest total sugar content (0.672±0.009 mg/flower), total nectar sugar concentration (38 per cent), energy per flower per day (11.24 J at 72 hours) and carbohydrate composition with glucose (53.12±0.015), fructose (36.21±0.179) and sucrose concentration (4.29±0.006).