The most dictyochophycean algae are unicellular flagellate but the members of the Rhizochromulinales possess amoeboid vegetative cells with filopodia. The dictyochophyceans are typically photoautotrophic but there are many mixotrophic (e.g. Pedinella) and colorless heterotrophic(e.g. Pteridomonas, Ciliophrys) species. They usually inhabit in marine, but freshwater species are also reported. Some species such as Pseudochattonella (= Verrucophora) and Dictyocha sometimes form blooms.

THe dictyochophycean algae typically possess single (no. 2) flagellum but the most members of the Florenciellales have two heterodynamic flagella. THe anterior flagellum is usually accompanied with wing supported by flagellar rod. The transitional region of flagella includes no transitional helix but usually proximal helix. At the anterior end of the nucleus, there is a depression in which the basal bodies are located. The dicyochophycean algae usually possess tentacles (axopods) supported by microtubules from MTOC on nuclear membrane. The cells are basically naked, but some species have organic or silicious scales or silicious exoskelton. No stigma. The major carotenoid is fucoxanthin thus the chloroplasts are yellowish. The heterotrophic species engulf particles without using R2. Asexual reproduction by means of binary fission. Some species produce cysts. Sexual reproduction is unknown.