In Bangladesh's northern and western regions, where maize (Zea mays L.) crops were already under threat from other pressures, particularly those brought on by climate change, the invasion of the fall armyworm [Spodoptera frugiperda (J.E. Smith); FAW] has compounded yield losses. From the present study, it was observed that application of the synthetic insecticides Ripcord 10 EC (Cypermethrin), Karate 2.5 EC (Lamda Cyhalothrin), Nitro 505 EC (Chlorpyrifos 50% + Cypermethrin 5%), Virtako 40 WG (Thiamethoxam 20% + Chlorantraniliprole 20%) and Neem Seed kernel Extract (Azadirachtin) compared to the untreated control, was effective and dramatically enhanced FAW larval mortality, decreased leaf degradation, and boosted biomass in maize. In the first round of spraying, both stay living larvae were identified on plants treated with Ripcord 10 EC (Cypermethrin), and in the second round of spraying; no live larvae were found on plants treated with Karate 2.5 EC (Lamda Cyhalothrin). After the third round of spraying, below one larva was found on all treated plants. The most effective synthetic pesticides are therefore recommended Ripcord 10 EC (Cypermethrin) and Karate 2.5 EC (Lamda Cyhalothrin) for the control of FAW in maize which will be planted in November-December in Bangladesh.