Mycosis fungoides is the most frequent cutaneous T cell lymphoma. Mycosis fungoides-related cutaneous T cell lymphomas include folliculotropic mycosis fungoides, with or without mucinosis, pagetoid reticulosis and granulomatous slack skin. Sezary syndrome is characterized by pruriginous erythroderma, adenopathies, atypical lymphocytes in the blood and a more aggressive course. B cell lymphomas represent 25 % of cutaneous lymphomas. Primary cutaneous follicle center cell lymphomas are the most frequent. They are often located on the head and trunk and have an indolent course. Primary cutaneous marginal zone B-cell lymphomas, which are more frequently multicentric and located on the limbs, also have an indolent course. In contrast, primary cutaneous diffuse large B-cell lymphomas, leg type, and primary cutaneous intravascular large B-cell lymphomas have a more aggressive course. Treatment must be adapted to each case. Unnecessarily aggressive treatments must be avoided in patients with indolent lymphomas.