Filamentous fungi comprise an industrially very important collection of mic
roorganisms, since they are used for the production of a wide variety of pr
oducts ranging from primary metabolites to secondary metabolites and furthe
r on to industrial enzymes (such as proteases, lipases and antibiotics). It
is known that fungal morphology is often considered as one of the key para
meters in industrial production. For the production of fungal metabolite pr
oducts, the desired morphology varies from one product to another. Many par
ameters affect the morphology of fungi during the process of fermentation,
among them speed of agitation, specific growth rate, dissolved oxygen, numb
er of spores or conidia per liter of fermentation broth are important and s
hould be considered when higher yield is desired in the process. It is, the
refore, of considerable importance to understand the mechanism underlying t
he morphology of the cell, its growth and product formation by filamentous
fungi. Such knowledge may be used in the optimization of the microbial proc
ess. Several literatures with various fungi to study their morphology, rela
ting enzyme or product production to the character of the fungi in the stud
y is reviewed. It is also considered that how the process parameters affect
s the morphology. The aim of this communication is to review the relevant l
iterature to understand the morphology of filamentous fungi.