Low-dimensional systems exhibit some of the most interesting physical phenomena seen in condensed matter physics. One-dimensional (1D) spin chain is important for understanding low-dimensional magnetism and useful for advancing quantum communications. In the present proposal we would like to investigate a slightly off-stoichiometric compound of this series Ca3Cu1-xMn1+xO6 (x = 0.07). The magnetic measurements and magnetic structure confirm ferrimagnetism in this compound (To=23K) and in our dielectric study we have seen anomaly at 100K in Ca3Cu1-xMn1+xO6 (x = 0.07), whose origin is not known at present. Muon spin rotation and relaxation (µSR) is a very sensitive probe to investigate magnetic ordering with very small moments and hence provides valuable information on magnetism when neutron diffraction does not give clear information on the nature of phase transition.