Abstract: Four myxoporeans of Leptotheca Thélohan, 1895 (Myxosporea, Ceratomyxidae) were found in blennioid fishes, red sea bream, black rockfish and false kelpfish collected from the Yellow Sea coasts1Amongwhich, a new species,Leptoth-eca brevoides sp1n1, three known forms,L1nebulifera Zhao & Song,-003,L1faba (Meglitsch, 1960) Zhao & Song,-003, and L1macrospora Auerbach, 1909 were investigated, which were newly reported by the present authors (Zhao & Song,-003) The species, including spores and plasmodia,were isolated in the urinary bladder or gall bladder of the hosts1The diagnostic features of Leptotheca brevoides sp1n1: trophozoites monosporous; small spore spherical or subspherical with smooth surface, (710-1010)μm &#-15;(615-715)μm in size; sutural line fine, two spherical polar capsules located anterior-ly, (210-215)μm&#-15;(115-210)μm in diameter; polar filament coiled-coils; coelozoic1Leptotheca nebulifera Zhao & Song,-003 is re-diagnosed as: trophozoites disporouswith filament like pseudopodium, (1110-1410)μm &#-15;(910-1215) μm in size; spore kidney-shaped with smooth surface, (1010-1-15)μm &#-15;(515-615)μ m in size; sutural line straight, two spherical polar capsules in a plane perpendicular to the sutural line, 115-210 μm in diameter; coelozoic1Leptotheca fa-ba (Meglitsch, 1960) Zhao & Song, 2003 is redefined by: possessing the thickness of spore less than or equal to, but not o-ver the height of spore, which was placed in genus Leptotheca; coelozoic1Pagrosomus major is the report of new host for L1faba1Leptotheca macrospora Auerbach, 1909 is redescribed as: trophozoites monosporous or disporous, spore kidney-© 1994-2010 China Academic Journal Electronic Publishing House. All rights reserved. http://www.cnki.net shaped with smooth surface, (18-26)μm ×(10-14)μm in size, two spherical polar capsules in a plane perpendicular to the sutural line, 3-4 μm in diameter; coelozoic.