Three bio-control agents viz., Pseudomonas fluorescens, Paecilomyces lilacinus and Trichoderma viride were evaluated for the management of potato cyst nematodes (PCN), Globodera rostochiensis and G. pallida under field conditions. Application of P. lilacinus multiplied on neem cake (containing 7 × 108 colony forming units (cfu)/g) @ 10 kg/ha and P. fluorescens in talc (containing 15 × 108 cfu/g) @ 10 kg/ha reduced the penetration of roots by the juveniles of potato cyst nematodes at 45 days after planting by 68.2 and 63.4 per cent respectively. Significant reduction in cyst count and egg population was observed in treatments that received P. lilacinus or P. fluorescens @ 10 kg/ha. The results revealed that these two treatments were equally effective in reducing the population of PCN and increased yield of potato significantly. The potato tuber yield was higher by 88.2 and 76.2 per cent (over control) respectively in Paecilomyces and Pseudomonas treatments.