Objectives. Determination of musculoskeletal ultrasound indicators characteristic for psoriatic arthritis, cutaneous psoriasis and rheumatoid arthritis. Material and methods. The cross-sectional study included 33 (36.66%) patients with psoriatic arthritis, 37 (41.11%) patients with rheumatoid arthritis and 20 (22.22%) patients with psoriasis vulgaris (without psoriatic arthritis), mean age 47±12.1 years. All subjects concerned informed consent, and the study received a favorable opinion of the Research Ethics Committee of the State University of Medicine and Pharmacy "Nicolae Testemitanu" on 21.12.2019 with no. 21. Results and discussions. The ultrasonographic manifestations in psoriatic arthritis are similar to those in rheumatoid arthritis, causing synovial hypertrophy, intraarticular effusion, Power-Doppler signal and erosions. Thus, joint damage in the studied patients was manifested by effusions (but without synovitis data), mainly in patients with cutaneous psoriasis (45%), as opposed to those with psoriatic arthritis (27.27%) and rheumatoid arthritis (37.83% – those with lack of synovitis data). Conclusions. Enthesis involvement is the main manifestation that differentiates psoriatic arthritis from other inflammatory arthritis, being frequently identified in the case of cutaneous psoriasis and never in patients with rheumatoid arthritis. Bone erosions were determined in both rheumatoid and psoriatic arthritis patients, with a significant prevalence in rheumatoid arthritis patients.