Amplification strategies using electrochemiluminescence (ECL) methodologies recently attracted considerable attention due to the need for ultrasensitive bioassays and the trend towards miniaturized assays. This review describes and discusses the amplification strategies in recent applications of ECL biosensors for cancer-biomarker detection, including detection and identification of DNA, single-nucleotide polymorphisms, small bioactive molecules, proteins and tumor cells. This work also addresses the future trends and outlook for signal amplification in ECL biosensors.