Objectives This study aims to evaluate the therapeutic effects of tenotomy and tenodesis of the long head of the biceps brachii tendon (LHBT) under shoulder arthroscopy based on the concept of enhanced recovery after surgery (ERAS) on long head of the biceps (LHB) tendinitis. Patients and methods Between January 2019 and January 2021, a total of 80 LHB tendinitis patients (44 males, 36 females; mean age: 55.3±4.5 years; range, 45 to 72 years) were included. The patients were randomly divided into the group of tenotomy of LHBT under shoulder arthroscopy (tenotomy group, n=40) and group of tenodesis of LHBT under shoulder arthroscopy (tenodesis group, n=40). Tenotomy group was randomly subdivided into Tenotomy-1 and Tenotomy-2 groups including 20 patients in each group to receive conventional treatment and treatment plan guided by ERAS concept, respectively. Similarly, the tenodesis group was randomly subdivided into Tenodesis-1 and Tenodesis-2 groups including 20 patients in each group. Their postoperative shoulder joint functions and pain were compared. Results The Visual Analog Scale score showed a significant difference between Tenotomy-1 group and Tenodesis-1 group at one, three, and six months after surgery (p<0.05). However, there was no significant difference at nine months after surgery (p>0.05). In the tenotomy group, although the operation time was shorter, the patients were more prone to develop Popeye deformity after surgery. The American Shoulder and Elbow Surgeon score, Western Ontario Rotator Cuff Index, Constant-Murley shoulder score had no significant differences between the tenotomy and tenodesis groups; however, there was a significant difference between the conventional treatment group (Tenotomy-1 group and Tenodesis-1 group) and ERAS treatment group (Tenotomy-2 group and Tenodesis-2 group) (p<0.05). Conclusion The clinical efficacy is similar between tenotomy and tenodesis of LHBT under shoulder arthroscopy. While selecting surgical approaches, comprehensive assessment should be performed based on all conditions of patients. Besides, therapeutic schedules should be upgraded and optimized with the help of the ERAS concept after admission to minimize the pain of patients, reduce the potential risk of surgery, and help patients recover quickly.