Background: This study intended to examine the association between the intrinsic and extrinsic motivation and knowledge sharing intentions among the nursing staff. Materials and Methods: It was a descriptive‑ correlational study, and the population included 860 nurses, working in Al‑ Zahra hospital, from whom a sample of 275 subjects were selected through convenience sampling method. The intrinsic motivation was composed of two sub‑ instruments, namely, the public recognition instrument (covering 3 items) and reciprocity instrument (covering 3 items), while extrinsic motivation included a knowledge self‑ efficacy instrument and an altruism instrument with 3 and 4 items, respectively. Moreover, knowledge sharing intention itself was evaluated a by 4‑ item inventory. Once the content validity, face validity, and construct validity (using confirmatory factor analysis), as well as the reliability (Cronbach’ s alpha) were confirmed, the model was analyzed through the partial least square technique. Results: There was a statistically significant association between both the intrinsic motivation and knowledge sharing intention (t = 14. 95, p < 0. 01, ) and extrinsic motivation and knowledge sharing intention (t = 3. 07, p < 0. 01). Moreover, it was found that knowledge sharing intention was positively associated with public recognition (t = 3. 98, p < 0. 01), knowledge self‑ efficacy (t = 3. 17, p < 0. 01), and altruism (t = 11. 44, p < 0. 01). However, the association between the reciprocal benefits and intention to knowledge sharing was not supported (t = 1. 77, p < 0. 05). Conclusions: The results indicate that both intrinsic and extrinsic motivations, including public recognition, altruism, and knowledge self‑ efficacy perceptions can be used to encourage knowledge‑ sharing practices among the nurses.