An attempt was taken to evaluate integrated management of Alternaria blight disease of radish variety BARI Mula-1 and quality seeds production in Bangladesh. Before setting the field experiment, invitro and in-vivo assays were laid out to select the virulent isolate AB-2 of Alternaria brassicae, antagonistic bio-agent Trichoderma harzianum isolate T-2, Neem (Azadirachta indica) leaf extract and Rovral 50WP (Iprodione) fungicide. The virulent isolateAB-2 of A. brassicae spore suspensions (5× 105 spores ml-1) was sprayed for inoculation purpose of radish field with micro-sprayer prior to flowering at 50 days after sowing (DAS). Bio-agent, T. harzianum isolate T-2 was used as soil amendment with wheat bran substrate (@ 90 gm-2), seed treatment (@ 3 g Kg-1) and also foliar spray (@ 5× 105 spores ml-1) at 3 times after 3 days of inoculation with A. brassiceae. Rovral 50WP was used as seed treatment@ 2.5 g Kg-1 seed. About 200 ppm conc. fungicide ((Iprodione) and 10% conc. Neem (Azadirachta indica) leaf extract was also used as foliar spry for 4 times at 10 days interval starting from flowering stage. The highest reduction of disease severity on leaf, siliqua and prevalence of A. brassicae on seeds (19.40, 15.40 and 10.00%) and increased seed yield and germination (160.96% and 85.45%) was observed in the treatment T8 followed by T7, T5 and T6, respectively. On the contrary, the lowest reduction of disease severity on leaf, siliqua and prevalence of A. brassicae on seeds (69.80, 62.20 and 43.22%) and decreased seed yield and germination (12.72% and 53.00%) was observed in the treatment T2 followed by T1. The intensification of seed yield was not only because of the reduction of diseases but also it might be due to addition of the bio-agent in the soil as a result, increases the number of soluble nutrients and provoke to secret the different growth promoting substances.