Objectives: To record Maximal Inspiratory Pressure (MIP) and Maximal Expiratory Pressure (MEP) in neuro-rehabilitation patients and establish correlation with functional status, quality of life, demographics and co-morbidities. Methods: Respiratory muscle strength was measured in 50 stroke patients and 50 spinal cord injury (SCI) patients. Both groups were evaluated with the Modified Barthel Index (MBI-Shah version) and the 36-Item Short Form Survey. Demographics, medical history, history of moderate physical activity prior to injury and American Spinal Injury Association (ASIA) classification were recorded. Results: Respiratory muscle strength declined with age and males exhibited higher MIP and MEP in the SCI group and higher MEP, but not MIP, in stroke. In the ASIA D SCI subgroup, the MBI total score was moderately positively correlated with MIP and MEP values. In stroke, MBI total score and MEP were positively correlated in both sexes and MBI total score and MIP in females. Diabetes mellitus absence correlated with higher MIP and MEP in SCI. Prior physical activity was linked to higher MIP, MEP in stroke and to higher MIP in SCI. Conclusions: Age, sex, functional capacity, SCI classification, quality of life components, history of physical activity and diabetes influence respiratory muscle strength in the studied population.