This study examined the psychometric properties of a newly developed instrument to assess psychosocial determinants of sleep hygiene. Baseline data (n = 160) from an m-health physical activity and sleep intervention were analyzed to examine scale validity. Additional participants (n = 20) were recruited to compute test–retest reliability. Four of seven constructs correlated significantly with sleep hygiene practice (r = −0.17 to −0.36). The scales generally displayed unidimensional component structures. Internal consistency was good to excellent (α = 0.76–0.92). Test–retest reliability was good to excellent (ICC = 0.61–0.84). Though satisfactory, these findings warrant replication in larger samples.