Objective: This study outlined the implementation and feasibility of delivering PROMIS® computer adaptive tests (CATs) using a web-based method to evaluate the impact of a technological adaptation of Cognitive-Behavioral Stress Management (CBSM) on the psychosocial functioning of men with advanced prostate cancer (APC) undergoing hormone therapy. Method: Patients were randomized to a CBSM group intervention (n = 95) or a health promotion (HP) attention-matched control condition (n = 97). Participants attended all sessions via video conference using tablets, and completed PROMIS® computer adaptive tests (CATs) assessing anxiety, depression, fatigue, pain interference, and physical function weekly during the 10-week intervention. Results: Assessment completion rates >50% at week 1 and week 10 demonstrated moderate feasibility of repeatedly administering PROMIS® CATs using a web-based method. Multilevel modeling demonstrated no significant group-by-time interactions from week 1 to week 10 for any of the assessed PROMIS® domains adjusting for sociodemographic and medical covariates. However, simple effects demonstrated decreases in PROMIS® anxiety scores from week 1 to 10 for both groups. Results also demonstrated significant relationships of medical variables to psychosocial functioning across time points. Conclusions: Results highlight the feasibility and benefits of utilizing PROMIS® CATs to repeatedly assess psychosocial functioning using a web-based method and indicate that web-based interventions may be effective for decreasing psychosocial distress and adverse symptoms among men with APC undergoing hormone therapy. (PsycINFO Database Record (c) 2019 APA, all rights reserved)