Chromosome pairing was light microscopically investigated by applying surface spreading technique in combination with 1-step silver staining method for the pachytene chromosome of artificial triploid transparent colored crucian carp (Carassius auratus transparent colored variety) with blocked ovaries. The triploid fishes were produced from hydrostatic pressure shock for fertilized eggs by inducing second polar body retention. The study was performed on the triploid females with blocked ovaries, one of many different types of females with various developing ovaries. Two subtypes were distinguished according to the presence or absence of primary oocytes. Meiotic prophase cells were not observed in the triploid females without primary oocytes. In the triploid females with blocked ovaries containing differentiated primary oocytes, the pachytene chromosomes were mainly composed of bivalents and unsynapsed univalents, and a few of trivalents and other multivalents were also found. There are about 90 chromosome elements including univalents, bivalents, trivalents and other multivalents in the pachytene cells. The size of chromosomes among different pachytene cells was obviously various. The pairing forks and specific synaptonemal proteins were clearly observed at some pairing and paired chromosomes. The relationship between disturbed chromosome pairing and blocked oocyte developing has been briefly discussed. The investigation also suggested that the artificial triploid fishes might be excellent materials for studying the mechanism of chromosome pairing and synapsing.