Idiopathic inflammatory myopathies (IIM) are a heterogeneous group of autoimmune diseases that primarily affect the muscles and skin but may also involve other organs, including the lungs, heart, and joints. They are rare compared to other autoimmune inflammatory rheumatic diseases. There have been changes in their classification criteria with the recognition that numerous autoantibodies play a role in disease pathogenesis. IIMs are currently classified into five main types: Dermatomyositis, polymyositis, overlap syndromes and antisynthetase syndrome, immune-mediated necrotizing myopathy, and inclusion body myositis. Autoantibodies implicated in IIMs are categorized as myositis-specific antibodies (MSA) or myositis-associated antibodies. Each MSA is associated with specific clinical and pathological features. Identifying these antibodies during diagnosis is valuable for both the treatment and prognostic assessment. For example, anti-Mi2 positivity is associated with milder disease courses and favorable treatment responses. Anti-MDA5 positivity is closely associated with rapidly progressive interstitial lung disease. In contrast, anti-TIF1-γ and anti-NXP2 antibodies are important risk factors for the development of malignancy. Early diagnosis and treatment are crucial for disease control. Most patients respond well to corticosteroids, while methotrexate or azathioprine are commonly used as corticosteroid-sparing drugs. If necessary, more potent immunosuppressive, biological agents, and intravenous immunoglobulin can be used. In this review, we summarized the recent advances in the understanding and management of IIMs over the last 10 years.