Field experiments were conducted during summer 2016 and winter 2016 -17 at Agricultural College and Research Institute, Madurai, Tamil Nadu, India to study the effect of intercropping systems and weed management practices on productivity and economics of irrigated cotton. The results indicated that, sole cotton and cotton + sesame intercropping system in 1:1 row proportion resulted in significantly higher seed cotton yield (SCY) of 1.43, 1.38 t/ha and 1.61, 1.56 t/ha, during summer 2016 and winter 2016-17, respectively and it was followed by cotton + sunflower intercropping system in 1:1 row proportion. The lower SCY was obtained with cotton + sorghum intercropping system in 1:1 row proportion. Among the different weed management practices, hand weeding twice at 20 and 40 DAS recorded significantly higher seed cotton yield. It was followed by pre-emergence (PE) application of pendimethalin at 1.0 kg/ha + hand weeding at 40 DAS. Considering the overall economics of the system, the maximum mean net return of  48822/ha and B: C ratio of 1.97 were recorded in cotton + sunflower intercropping system with PE application of pendimethalin at 1.0 kg/ha + hand weeding at 40 DAS. This was closely followed by cotton + sesame intercropping system with PE application of pendimethalin at 1.0 kg/ha + hand weeding at 40 DAS. Intercropping of sunflower and sesame in cotton with 1:1 row proportion found remunerative over sole cotton.