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Objective Objective To investigate the changes in hippocampal astrocytes and neuronal primary cilia, and neuronal apoptosis in the offspring brain of advanced maternal age and the role of LKB1/AMPK pathway. Methods The 12-month-old SD female rats were mated with 3-month-old SD male rats to produce offspring as the advanced maternal age (AMA) group, and the 3-month-old SD female rats were mated with 3-month-old SD males to produce offspring as the appropriate age (Control, Ctl) group. The following studies were conducted on postnatal days 14, 28 and 60 (P14, P28 and P60) in the 2 groups (14 rats per group at each time point, half males and half females). HE staining and Nissl staining were used to observe the changes in the morphology and the number of hippocampal neurons and their internal Nissl bodies. Immunofluorescence assay was employed to detect the expression of hippocampal primary cilia marker, anti-ADP ribosylation factor-like protein-13B (ARL13B), and Western blotting was applied to measure the expression of hippocampal intraflagellar transport protein 88 (IFT88) to assess functional changes in primary ciliogenesis. TUNEL staining and Western blotting were performed to detect the expression levels of pro-apoptotic BAX, and anti-apoptotic protein, BCL-2 to observe the changes of apoptosis in the hippocampus. Western blotting was also used to detect the expression levels of liver kinase B1 (LKB1), adenosine monophosphate-activated protein kinase (AMPK), mammalian target of rapamycin (mTOR) and the levels of their corresponding phosphorylated proteins to assess LKB1/AMPK pathway changes. Results Compared with the Ctl group: HE staining and Nissl staining showed that the number of hippocampal neurons was significantly reduced in the AMA group at P14 (P < 0.05), and there were abnormal changes in hippocampal neuron morphology and Nissl body number and morphology in the AMA group at all time points; the incidence of ARL13B primary cilia was significantly decreased in the AMA group at both P14 (P < 0.05) and P28 (P < 0.001), and the length of ARL13B was obviously shortened in the AMA group at both P14 (P < 0.05) and P28 (P < 0.05); the hippocampal expression level of IFT88 was notably lower in the AMA group at the P14 (P < 0.01). TUNEL staining showed that the apoptotic rate of hippocampal neurons at P14 was remarkably higher in the AMA group (P < 0.05), while Western blotting indicated that the expression of BAX was significantly higher (P < 0.001) and that of BCL-2 was lower (P < 0.01). In the AMA group, the expression of p-LKB1 was significantly decreased at P14 (P < 0.05), that of p-AMPK was statistically elevated at P28 (P < 0.01) and P60 (P < 0.01), and that of p-mTOR was notably decreased at P60 (P < 0.05). Conclusion Neuronal damage, defective primary ciliogenesis and growth inhibition, and abnormal activation of apoptosis are present in the hippocampus of juvenile offspring brain of advanced maternal age. Meanwhile, the LKB1/AMPK pathway, which is regulated by primary cilia in hippocampal astrocytes and neurons of advanced maternal age offspring brain, is abnormally activated at all ages.