卡哈尔体（英语：Cajal body，或译柯浩体），是存在于细胞核里的细胞器。卡哈尔体是相当具保留性的核细胞器。到目前为止，在脊椎动物、果蝇、酵母菌，以及植物中均发现存在卡哈尔体。尽管卡哈尔体被发现已经100多年，卡哈尔体的确切功能还不是很明朗。初步证据显卡哈尔体可能与参与mRNA剪接的「snRNA－蛋白质复合体」的成熟有关。

1903年，西班牙医学家圣地亚哥·拉蒙-卡哈尔用高尔基染色法在兔和人的神经元细胞核内发现着色的除核仁外，还有一个黑点，他称之为「核仁附属体」（nucleolar accessory body）。之后一些科学家在其他生物的细胞核发现类似的结构，并给以不同的名称。直到1999年，美国细胞生物学家Joseph G. Gall建议将这些相同的核细胞器重命名为“卡哈尔体”以纪念它的发现者。

Cajal bodies (CBs) are spherical sub-organelles of 0.3-1.0 µm in diameter found in the nucleus of proliferative cells like embryonic cells and tumor cells, or metabolically active cells like neurons. In contrast to cytoplasmic organelles, CBs lack any phospholipid membrane which would separate their content, largely consisting of proteins and RNA, from the surrounding nucleoplasm. They were first reported by Santiago Ramón y Cajal in 1903, who called them nucleolar accessory bodies due to their association with the nucleoli in neuronal cells. They were rediscovered by electron microscopists and named coiled bodies, according to their appearance as coiled threads on EM images, and later renamed after their discoverer. Research on CBs was accelerated after discovery and cloning of the marker protein p80/Coilin. CBs have been implicated in RNA-related metabolic processes such as snRNPs biogenesis, maturation and recycling, histone mRNA processing and telomere maintenance. CBs assemble RNA which is used by telomerase to add nucleotides to the ends of telomeres.