Background: Neurological dysfunction like guillain barre is a common condition necessitating prolonged mechanical ventilation (PMV). Inspiratory muscle weakness is common in these patients which may cause failure of weaning. Purpose of this study: To compare the effect of both ventilator inspiratory trigger sensitivity adjustment and threshold device training on difficult to wean guillain barre patients. Material and methods: There were 30 male and female (23 women &7 men) patients on mechanical ventilation who had guillain-barré syndrome with an age range of 25 to 55 years old took-part in the study. Twenty-six of these patients fully completed the study while three of them died and one was re-intubated. They were recruited from neurological intensive care unit (ICUs) in Al- kaser Al- ainy medical school, Cairo university. The practical work of the study was carried out in the period starting from January 2022 to December 2022. All patients were randomized into two study groups; group (A) threshold inspiratory muscle trainer was used and group (B) changes in ventilator pressure setting. Primary outcome was time to complete weaning (in days), secondary out comes were changing in mechanical ventilation sittings including: Negative inspiratory force (NIF), Inspiratory positive air-way pressure (IPAP), Positive end-expiratory pressure (PEEP), Minute ventilation (VE), Respiratory endurance (Index of Tobin), and the PaO2/FIO2 ratio. Results: After management in both groups the results of primary outcome indicate a statistically significant change in the MV group that patients spent substantially fewer days on a ventilator on average (9.27±4.74) compared to the IMT group (16.67±6.86) with a t test = -3.436 (p=0.002). Also there were no significant differences in NIF, IPAP, PEEP, Index of Tobin, and PaO2/FIO2 levels between the MV group and the IMT group. There was a borderline significant difference in minute ventilation (MV) between the MV group the IMT group. Conclusion: It could be concluded that inspiratory muscles training by ventilator inspiratory trigger sensitivity adjustment helped to reduce days on mechanical ventilator more than threshold device training, with no significant differences between two techniques regarding to ventilator variables in difficult to wean guillain barre patients.