Objective To explore the barriers to clinical skill learning among intern nursing students, and to provide a reference for clinical nursing teachers to formulate preceptorship strategies. Methods A descriptive qualitative study was designed based on the four processes of observational learning theory: attention, retention, reproduction, and motivation. A total of 21 intern nursing students were purposively selected, and semi-structured interviews were conducted. Data were analyzed using directed content analysis. Results Four core themes and 11 sub-themes of learning barriers were extracted: dual deficiency of demonstration and attention (non-standard preceptor demonstration, frequent clinical interference, insufficient attention focus); broken chain of memory and consolidation (weak knowledge reserve, lack of memory association, absence of review mechanism); dual blockade of practice and feedback (insufficient operation opportunities, delayed and vague feedback); dual weakening of reinforcement and identity (inadequate reinforcement mechanism, excessive psychological pressure, low professional identity). Conclusion Barriers to clinical skill learning among intern nursing students exist throughout the entire observational learning process.A systematic "precise de-monstration-systematic review-stepwise practice-diverse motivation" four-in-one intervention strategy should be targeted to overcome barriers at each stage and improve nursing students′ clinical skills.