Investigations into new treatments for immune-mediated dermatological diseases like psoriasis, atopic dermatitis, alopecia areata, and collagen tissue diseases are ongoing. JAK inhibitors are showing promise in clinical trials due to their oral administration and cost-effectiveness. Both the number of these compounds and clinical trials have increased recently. While some show promise, more research is necessary for their clinical application. Notably, deucravacatinib is FDA-approved for psoriasis treatment, filgotinib is approved for rheumatoid arthritis (RA) treatment in Europe and Japan, and peficitinib is approved for RA treatment in Japan. Long-term side effects and comparative efficacy remain subjects for further exploration. This chapter will review the mechanism of action, indications, and current evidence for these novel JAK inhibitors.