Cross experiments between the artificial pigmentation mutants and the wild type in Porphyra haianensis Chang et Zheng, were＂ carried out to examine the occurrence of meiosis in its life history, according to the appearance of color segregation and colorsectored blades in the F1 gametophytic blades developed from the conchospors of the heterozygous conchocelis. Two red types of pigmentation mutants （ SPY- 1 and R-10） were used as female parent, and their blades show red or red orange in color, thin and weak elasticity and have no denticles on their marginal parts. The wild type （wt） was used as male parent, and its blades show wild-type color, thick and good elasticity and have many marginal denticles. Among the Fl gametophytic blades from the crosses of SPY- 1 （ ♀ ） ? wt（♂） and R - （ ♀ ） ? wt（♂）, two parental colors （R and W） and two new colors （R＇, fighter in color than R; W＇, wild- type-like color and redder than W） appeared. Linear segregation of colors occurred in the blades, and therefore, the color-sectored blades with 2 - 4 sectors were formed. In the color-sectored blades, the sectors of R and R＇ were thinner than sectors of W and W＇, showing weak elasticity and without marginal denticles. However, the sectors of W and W＇ were thick, showing good elasticity with many marginal denticles. 95.2% -96.7% of the F1 gametophytic blades were color-sectored blades, and only 3.3% -4.8% of them were single-colored blades. These results indicated that the meiosis of P. haitanensis occurs during the first two cell divisions of the germinating conchospore, and thus it was considered that the initial four cells of the developing sporeling constitute a linear genetic tetrad leading to the formation of the color-sectored blades. The new colors of R＇ and W＇ were recombinant colors because the occurrence of chromosome recombination during the first cell division of the meiosis. It was certain that the color phenotypes of two mutants used in this paper resulted from two or more mutations in different genes, and that they also have mutations relative to blade thickness and formation of the marginal denticles, which is linked with color mutations. The recombinant colors of R＇ and W＇ were better in contents of chlorophyll a （ Chl. α ）, phycoerythrin （PE） and phycocyanin （PC）, and growth and maturation, indicating that the improved varieties probably could be obtained through crosses between the pigmentation mutants or between the pigmentation mutant and the wild type in P. haitanensis.