Camptothecin (CPT) represents a clinically useful class of anticancer agent. Proper identification and quantitation of the CPT in the plant extracts and in-vitro cell culture extracts is fundamental to assess the CPT content and its biosynthetic potential in plants. A simple, sensitive and rapid, spectrofluorimetric method has been developed and validated for the quantitative estimation of camptothecin. The method was validated in terms of linearity (2-20 ng/ml), precision (intra-day variation below 0.15, interday variation below 1.2), and accuracy (98.0 to 100.2%). The limit of detection and limit of quantification for CPT were found to be 0.10 ng/ml and 0.36 ng/ml, respectively. The developed spectrofluorimetric method provides a rapid and cost effective method for the routine analysis of CPT in plant extracts and tissue culture samples. The developed method was successfully used for the estimation of CPT in natural plant extracts and cell culture extracts. The Nothapodytes nimmoniana callus cells having nearly 3-fold higher CPT content over the leaf (0.005%) explant of the plant. The highest CPT content was found in the stem part (0.092%) followed by the fruit (0.088%). The method is simple, sensitive and precise; it can be used for the routine quality control testing of formulations containing CPT.